* Instead of a library of songs to listen to, you're listening youtube videos without the video. I make playlists with them and songs disappear randomly.
* The player is buggy. The music will skip, or randomly restart. Randomly a song won't play because it says the format isn't supported (which doesn't make any sense), and then the playlist stops altogether.
* In Google Play Music, you Liked songs and they would be in a Liked songs playlist. In Youtube you like videos and they are in a Liked Videos list. In Youtube music, after you've merged it, you now have a Liked list that is both your music from GPM, and every Youtube video you've ever liked that's also a song.
Youtube music is a drastic step backwards from GPM. I would've left for spotify already. but I appreciate also having Youtube without ads, and I don't want to pay for both services. I would've been happy with GPM sticking around forever with next to no updates, but Google always has to change something so managers can get their raises and promotions.