I've been a Plex-to-Jellyfin convert for a long while now, and I've nothing bad to say. I switched because Plex kept pushing their streaming services, and the fuzzy feeling I get from running FOSS.
Jellyfin used to run on my desktop which has a beefy CPU/GPU, but runs fine on my puny Synology NAS.
How much of your use is audio streaming? I'm dying to make my collection remotely accessible after leaving the Plex ecosystem.
Just try Navidrome!
i use navidrome but no folder view, so mixtapes with many artist is counted like many albums
maybe you could try
https://github.com/sentriz/gonic
(nightly build)
it supports browsing by folder