Exactly. I used XBMC and then Kodi for years until I got a smartphone and a laptop and wanted to keep my watched list synced across multiple devices. It was way too complicated with Kodi; it was never designed for that. That’s when I switched over to Plex.

Aside from that use case, though, Kodi is an incredibly powerful and impressive piece of software.

Kodi has a plugin called "plexkodiconnect" that uses plex as the media backend for kodi front ends. It basically replaces the kodi media db, giving you updates/sync/resume/intro skip/etc the same way plex does. Plex runs on a server as normal, and can be used however you normally use it as well. Youre still able to use plex apps on whatever devices you like.

You get the best of both worlds with some light setup.

I think Jellyfin is only an overkill if you don't value privacy

Kodis had that for ages if you can run a small Maria or mysql server to host the databases. Plex makes that process easier for sure, but Kodi can do it.