As someone currently running a Navidrome instance with 40k songs...yeah, I wouldn't wish that on anyone(horrible performance), but it is an option I suppose.
The second issue isn't specifically a "Navidrome" problem, but every iOS and Mac desktop client I've used(and I've tried _every_ one that Navidrome lists on their site) attempts to load every song on load and basically becomes unusable.
I'm about two notches away from writing my own music streaming server. Navidrone is barely functional for me...and falls under software I hate, but there are no better options.