Those are the the ones that somone has managed to find in closed source software...
Mondez
I don't think it is that is more polished, it's just you pay for them to do the stuff you need to do yourself with reverse proxying, opening ports, securing stuff. This is only an issue if you are sharing outside your network of course.
Why bother self hosting at all then? Paying somone else to do it for you and the deal constantly getting altered is pretty what you signed up for.
That's because you had somone elses servers doing that part for you.
Fully aware and autonomous? Sounds like AI talk to me...
It's a donation that is deceptively framed in my opinion, bit of a dark pattern, but the product is fully open source so most give it a pass.
I've not looked into it but presumably it's because whatever web server framework they are using might not be as bug free and battle tested as dedicated web server application like nginx so by limiting the actual web servers exposure you are limiting the attack surface.
You are forgetting the arcane patterns we have to engrave on them too.
Worse they often report issues that affect them but still don't commit resources to resolving those issues.
They run their own full OS these days on under powered SoCs to cut costs. All so they can claim to be a "smart" TV until of course the flow of updates stops a year after manufacture and all the apps stop working. Then it's back to being dumb as well as being a massive security hole on your network.
That was a long winded way of saying you don't know what Jellyfin actually is or does. Mpv is a client, it only fills the role that the various Jellyfin clients perform and a better comparison would be against a heavier weight media player such as Kodi.
What you suggest works well enough if you have a reliable network link to share CIFS or NFS over, but what do you do when away from home on a rubbish link that doesn't have bandwidth to stream all your high quality bluray rips? You want transcoding in that situation.
Also, I'm a seasoned Unix sysadmin who knows his way around the cli and I can say with certainty this isn't for people who know the cli, it's for people who just want to prove you can do anything from the cli even if suboptimal.
Capitalism can work well when it's coupled into a virtuous circle of funding R&D to create new products and services to increase income to put back into more R&D.
At the moment it seems that a lot of companies are just trying to seek ever increasing rent extraction on existing products rather than investing in trying to innovate and relying on high barriers to entry to keep competition out.