I tried putting up SearX and NextCloud, without really having used any equivalent cloud services in the past... but eventually both came unstuck, because:

• SearX ended up getting blocked by basically every search engine, even though it was a private instance and only I was using it. And even while it worked, the results were not much better than using some other engine like Brave Search or even Startpage. Also, being the only user on that IP, meant that I was still able to be tracked by Google and filter bubbles started being an issue.
• NextCloud - just wasn't a need for it. I initially used the RSS reader and email and a few other things, but I already have a good desktop email client and RSS reader and preferred to use them, and other services I just wasn't that interested in. No point putting in the effort maintaining it if I'm not using it.

These were personal instances though. Maybe might have been more successful if I'd had a userbase to serve, who actually were interested in having things web-based and were not so concerned about the inevitable loss in performance compared to desktop apps.