I run Plex and am pretty happy. Will likely eventually switch to Jellyfin as Plex is getting lamer and lamer.

I’ve been a Plex user since the early days. I currently run it on a Synology NAS in a container, using the Plex app on the AppleTV as my primary client device. I tried setting up a Jellyfin container a few months ago as I’ve been concerned about the direction of Plex. It went poorly.

I have a fairly large library, which Plex never seemed to care about. Jellyfin choked. It took forever to go through it all, and I seem to remember questioning of it was working; it wasn’t clear. Plex on the other hand makes it pretty entertaining to watch covers flip over as the metadata is loaded in to see the progress. Then every app I tried on the AppleTV also seemed to have trouble. The one that worked best had to create its own local cache of everything, which required I spend hours browsing to every screen and waiting before it became reasonably smooth. After that, the layout was still pretty strange. I think it would have worked just as well to point it at a file share. Actually playing videos was hit and miss in every app I tried.

I’m still using Plex. If I need to move to Jellyfin at some point, I feel like I’ll need to build a server with a lot more power than Plex requires. Of course that’s just a theory… a theory that will be expensive to test.

For all the fanfare Jellyfin gets online, I expected it to be better. It made me question how honest the people pushing it are. But maybe they have small libraries or only tested it with 5 movies for the review. I don’t think that’s a real-world experience.

Jellyfin's worst aspect is the opinionated file structure. You have to set up folders the way it wants, and then the resulting UI browser is what-you-see-is-what-you-get. Pretty sure it's done this way for automated metadata discovery.

Ideally, this would be designed in two parts: separate the file structure from the metadata discovery mechanism.

I personally want a file structure managed by the OS. Let me make folders and nested subfolders to whatever structure I prefer.

Then make the metadata discovery slightly more manual. Click a media file, click a hypothetical "add metadata" button, and then a simple search box with "is this your movie?" and click apply to import metadata from a search result. easy peasy.

The UI is clearly meant to resemble a typical media app but falls short if the end user prefers, for example, foobar2000's UI.