Definitely not just for handhelds. Check out Universal Blue images which are built ontop of Fedora Atomic (the immutable variant). Bazzite is an awesome gaming distro that's rock solid. Bluefin is awesome for Devs and more technical people. But even for non-devs it's awesome since the images are purpose build with and without all the devs tools. You pick your preferred DE (KDE or GNOME), and your graphics drivers.

Almost everything is setup for you that you would have to do mannually compared to Fedora Atomic, and additional quality of life tweaks are included as well.

Been running, Bazzite on my gaming rig for months now and it's been great. Running the Cosmic/Gnome UBlue image on my framework laptop for months and its also been amazing.

If I were to go immutable and I wanted good gaming support I'd probably opt for Bazzite It's atomic and it's focus is being a base for a great for gaming, Chris Titus ran it recently (and killed it in good titus fashion) and the outcome was really really good.

But, it sounds to me like it's more adapted for smaller devices and IoT, like the Steam Deck or similar handheld devices.

There are plenty of desktop focused immutable Linux distros. With Fedora Sikverblue/Kinoite probably being the most prominent one, but there are also Vanilla OS, the ublue distros and the one I'm personally using, (openSUSE) Aeon. NixOS technically counts too I think, but that one has it's whole own philosophy/structure that extends way beyond just being immutable

What were the pros and cons according to you?

Pros: increased stability/less risk of breakage, sepaeation of base system/apps that will be more intuitive to many non-Linux users, (Flatpak) apps tend to always be the newest version
Cons: still some smaller pain points around app integration, some flatpaks might have some features that don't fully work or you might need to change a permission (this has gotten a lot better already though), less suited for tinkerers

No, the device size doesnt matter at all.

Sounds you only saw Bazzite, which would be my recommendation if you want good Windows app compatibility.

I personally use the official Fedora Kinoite but it is a lot more barebones, and I change quite a bit.

I recommend to try Bazzite or Aurora, it just works. Poorly, because Fedora people make strange decisions, and also leave out too much, I cant recommend vanilla Kinoite for beginners.

I just made a post on how I setup Silverblue and I will do one on how I actually setup my main Kinoite.

That will be bigger, as I have a ton there.

I have my dotfiles, which contain configs, here on Github.

Also have a look at these posts

I really like the concept of immutable/atomic distros, but right now its just not a super viable option for me. Every time I've tried one, there's always been something that I felt like I either couldn't install, or ran into a lot of resistance installing. Something super basic for example is OpenRazer in order to control the settings of my mouse and keyboard - the backend of OpenRazer exists as a DKMS module, and kernel modules seem to be a bit more difficult to install on an atomic distro than a "mutable" distro.

Most atomic distros have some sort of escape hatch/"break glass in case of emergency" way of installing packages directly (such as layering with OSTree distros), but those tend to have their cons and also feels like its going against the whole point if I end up having to use it a bunch.

NixOS was interesting, but I just don't have the time to learn Nix, I've tried on multiple occasions and get mostly there with configuring my system how I want... and then there's something that just doesn't work and ends up being a deal-breaker for me.

I think the endgame solution for me would be to look into something like blue-builds so that I can "craft" my own image, but again, time is the limiting issue for me.

That all being said, just because it doesn't work for me personally, that doesn't mean it won't work out for you - I'd advise anyone to give it a try if their interested.

I ran Fedora Silverblue for the past few months. The selling point that convinced me was that the system you install is the exact same the developers use for testing.
I also hoped it would just update itself without any intervention. And I was fine with default Gnome and Flatpaks.

My experience was that it actually offered no real world benefit. Arch had fewer visible bugs. It crashed a few times, in a way that the only way out was cutting power. The auto-update didn't work, I still had to manually check for updates and click "install", and every update requires a reboot. Sometimes it needed 2. Video streaming was jerky even in the flat hub version of Firefox.
And it's pretty limiting: Many command line tools I'm used to were missing, even Gnome Tweaks was missing (WTF?). Of course I could "layer the image" and alter it to include what I need, but that defeats the entire purpose. And system tools don't work well in containers, either.

There's basically no in-depth documentation on how to do stuff that is standard on other distros but now doesn't work the same due to the immutability. And it had just too many inexplicable quirks to use it as a zero maintenance grandma OS.

I switched back to Debian. Installed just the minimum required base system, the minimum required packages to run Gnome shell, and got all my software from Flatpaks. It looks basically the same, is more stable and bug-free, and I can tinker on the command line if I feel like it.
I made an

alias Upd="doas apt update && doas apt dist-upgrade && doas apt autoremove --purge && flatpak update"  

which is so much faster than using the gnome software center.

I asked the same question a few months ago and landed on installing Bazzite myself. Couldn't be happier! It's a very hassle free experience and everything just works as intended. Love how the system and software just automatically updates upon a reboot. Wholeheartedly recommended! 🙌

But I’ve been looking at immutable distros as a more stable alternative.

If "stable" is used in the context of "intended use entails no changes/updates to packages found in the repositories in between 'long supported' point releases"^[1]^, then it's important to note that an 'immutable' distro as such does not exist; or at least is far from mainstream*.

If, however, "stable", instead, is used in the context of "less inclined to cause breakage upon (perhaps more frequent) updates", then indeed; 'immutable' distros can definitely be beneficial. Heck, I would even argue that they are successful at providing more stable experiences. This is actually implied merely by design. And, thankfully, the 'immutable' distros have been able to deliver on this promise.

But, it sounds to me like it’s more adapted for smaller devices and IoT, like the Steam Deck or similar handheld devices.

They, indeed, make a lot of sense for these use cases. However, the use of 'immutable' distros on desktop is also pretty well established. Even if it's currently (relatively) niche.

Have you installed an immutable distro on your PC?

Yup. Over two years ago, I switched cold turkey from Windows to Fedora Silverblue without any prior Linux experience. I've been very happy with it ever since. However, since over a year, I've been on uBlue. These are recommended over Fedora's own images for a multitude of reasons; one of which being better on-boarding.

What distro did you use?

As previously mentioned; Fedora Silverblue. Back then, and even today, Fedora Atomic has been one of the most mature iterations. Other mature 'immutable' distros (i.e. Guix System and NixOS) require a lot more know-how by comparison.

What was your experience like?

I simply don't see myself use traditional distros beyond special use cases. Literally all of my experiences with (semi-)rolling traditional distros^[2]^ (that I have engaged with through dual booting) ended with an unbootable system. By contrast, besides my first week, I can't recall the need to resort to Fedora Atomic's built-in rollback functionality to combat a non-booting system. It's just been such a pleasant experience.

1. Besides those related to security.
2. Which include the likes of Arch, EndeavourOS and Nobara.

I run Bazzite on an old 2015 laptop that has an onboard Nvidia 960M and an Intel processor (4th gen i3). Works great, and having dealt with bad updates in the past, I have a lot of peace of mind (I've even done a rollback when an upstream bug came through, and I was able to continue having a working system).

I will caution you that VPN clients can be tricky to install, depending on how they package their software. OpenVPN and WireGuard are installed by default, however, so if you can get the necessary config files, you can do it through the usual NetworkManager.

From my personal testing experience I would say the concept is solid but the existing distros are not there yet, with some missing features, minimal documentation and several rough edges in their containerisation approach (as in: some features and things not working because the container wasn't well adapted to the immutable OS yet).

A lot of people use Bazzite, but i’ve switched my systems to Nix, and so far i’m very satisfied. The learning curve is colossal, but i feel like once you figure out what you need, it’s absolutely worth it

I'm upgrading my father-in-laws 2011 imac (Intel, amd GPU) to an ssd, 16GB ram, and planning on putting an immutable linux OS on it for him since he primarily uses the browser anyways.

Any recommendations for non-techy seniors/gotchas for installing it on a mac?

I was thinking fedora silverblue since GNOME should feel more familiar than KDE for him.