Well it works perfectly on my Pixel 3a. As with 'Play music' when I select 'Device files' all my MP3 tracks are loaded up and I can select either 'Songs' in which case all 400 (currently) or so will be played, or 'Artists' in which case I can select one and play all their tracks from all their albums or 'Albums' in which case I can select one of my albums and play it.
So I don't understand what your problem is, unless you are referring to downloaded 'YTMusic' which, as with 'Play music', I don't subscribe to, I use it as a 'player' for my MP3 collection. Even so I would be very surprised if the options are different.
'YouTube music' is certainly not 'garbage' as far as I am concerned.