Actually Apple Music offers exactly this. There might be other reasons you'd prefer not to use it, which is fine, but in terms of offering they're actually quite similar.
Except Apple will actually allow you to upload more songs than Google Music, up to 100,000.
I did really like Google Play Music, and allowing the local library sync as a free draw was a really smart move. But the sour taste they left in my mouth by killing my discount plan and ruining the UX meant I looked at other options. Signed up for Apple Music day one and it has improved leaps and bounds since then.
It's very clearly a huge priority for Apple, and they aren't resting on it.
works on linux and there's also an unofficial API
https://unofficial-google-music-api.readthedocs.io/en/latest...
I make playlists almost daily for work and I use the API to manage them, dedupe, delete old ones, and what not. Super convenient.
But the web UX has gone to crap. There was an update a few months ago that really killed its performance and broke the playlist sorting. They need to eat some of their dogfood.
The thing is, the paid tier of GPM is really only for on-demand streaming of the music catalogue and removing ads in the radio. As an upload-only user, I really see no reason to pay money for a service that I am fully enjoying for free. If Google were to add back (and continue developing) the removed My Library features and decide to make a payment tier for use-cases like mine, I'd happily subscribe. Their focus on "your library anywhere, with extra features" is something that really stands out. I'd hate to see GPM turn into just another stream-what's-licensed service.