Edit: so it turns out that every hobby can be expensive if you do it long enough.
Also I love how you talk about your hobby as some addicts.
Why?
I admit I don’t know anything about jellyfin but Plex was dead simple to set up.
It’s free and just as easy. You miss a few plex only features but they’re not worth their money. Although I did get a lifetime license for 75$. Otherwise plex is too expensive if it’s the monthly sub for the pass. Feature wise, but thats probably personal.
So far I haven’t found the Plex pass to be necessary for me at all. I torrent my media and that’s it. I have Apple Music for my music, which allows for lossless downloads, I don’t care about skipping credits, and love tv doesn’t matter to me at all. Since the free tier with Plex serves my needs well, I’m not sure why I should look at Jellyfin when by all accounts it’s more difficult to use and I’d have to make my friends switch to a new means of accessing my library.
It’s open source and gives you a lot of fantastic features that are locked behind paywalls and more on plex. But I will be honest it’s not nearly as simple and setting it up so I could use it outside of my home network took a week of figuring out issues with proxies.
You can keep using plex but if you have a good tech understanding jellyfin is pretty nice.
For your computer troubles I would say you can skip the pi completely if you have the space and get something like a cheap optiplex. They are dirt cheap used and can give more oomph and customization for hardware later on and are really simple to get any Linux distro on.