> I have no idea on when artists I like release new albums and would not encounter them on a self hosted solution, etc.

Depending on what you like, bandcamp makes it easy. You can follow any artist (which is also offered whenever you buy), and from then on get release notifications. But of course, what’s available differs by genre. For metal, most bands are on BC, except most Japanese artists and major label stuff.

I buy, download, and put the flacs on my Jellyfin server.

There are, of course, also piracy solutions for that, pretty sure the *arr stuff has automatic downloading per artist.