I used Google Play Music for purchases/online music locker and loved it. I eventually became that idiot that never downloaded all their purchases before the switch to Youtube Music happened.
Now I can't even open Youtube Music because it loads up my GPM library and rubs in my face that I essentially paid to have a bunch of music pre-listed for streaming that now has unskippable ads that I can't listen to unless I leave my screen on and unlocked.
I was too broke and slammed to get a new external drive in order to get all my music downloaded and saved from GPM at the time of the switch, but I look back on it and think about how I could've skipped meals and stuff to have gotten something with just enough space to save that music.