Just sent in the following feedback, feel free to copy & send this, too:
Currently for songs and albums, you can mark them as "Disliked", but you can't mark an entire artist as Blocked, only Follow.
I want to extinguish ThWknd, Drake, and a bunch of other terrible "artists" from existence, never see them in my For You page, never be recommended them in any page.
Ideally once I Block an artist, they wouldn't even show up in searches or in your curated playlists.