I’d probably find the music you’d want, download it without a DRM (where it’s lawful to do so), and self-host it. Then, when you want it, you can find your music on said self-hosted solution, copy and and import it to different local-first music players. On Android, I can’t recommend Sono Beta enough. On iOS… I need to look for a local-first solution that isn’t compromised by Big Tech.
For Linux, since you’re on Fedora, maybe I’d look for either Audacious or QMMP (either or is Winamp-like if you’re into that), since they look similar. Otherwise, you could potentially use something like Rhythmbox (I listen to podcasts using Rhythmbox with RSS feeds) or similar to that. I heard Fooyin was good as well.