https://www.discogs.com/company/discogs-database-artist-page-improvements-2023
https://www.discogs.com/forum/thread/1017930
Looks like it’s final now and no more way to switch it off. Discogs import userscript also partially broke 
Meanwhile their forum is having a meltdown:
What exactly broke for you?
Artist pages have less MB links now. Each alias used to have a link to the MB artist or search, same for the release list
Ah … I see … I noticed this also … but the importing of a specific release still works for me at least … let’s see how long this will work
Maybe this is as easy to fix as when Discogs rolled out the release page redesign, but I don’t have the time to investigate that now.