You might check out wiim stuff. They seem to be the darling of budget streaming for the moment.

There have been a few mentions of Navidrome. I find it works well for sharing at an album or even artist level. It can do playlists as well. But you must explicitly choose what to share, at which point it’s generates a unique URL and will generate a web player and zip if you enable the option to download.

You can, of course, just make user accounts and distribute credentials.

If you’re needing to offer browsable folders to easily copy, basically a filesystem-like experience, it’s probably not the best tool.

Edit: one more thing to point out is that navidrome, jellyfin, and airsonic all construct music libraries differently. Navidrome is using tags, jellyfin uses file names, airsonic uses directory structure. Not sure about Plex.

for that I expect to get that)

Only thing I can say on 3 is the interface is pretty not bad. I’ve never quite liked it, but it has never really gotten in the way. I only recently started trying the track/artist mix. Also can say it’s okay. I’ve actually found a few gems over a few weeks of usage, but at the same time I have found times where it’s time to skip to the next track, though this is mostly due to personal taste and not because it’s throwing some really out of character into the playlist.

Tidal has been pretty good for me over the past 5 years. I don’t know what your criteria are, but for me it’s something like 1) is the catalog big enough to offer 90% of what I’m looking for and 2) no advertising if I’m paying for the service. It ticks those boxes. I imagine it’s only a matter of time until they introduce the bullshit tier where you’re paying and being advertised to, but for now you get what you pay for.