An good place to start on the topic of how the art world was corrupted and much beauty suppressed or discouraged is the article "Berg, Berg, and Berg" from Instauration magazine:

National Vanguard

Berg, Berg, and Berg

TOM WOLFE has written an entertaining and ironic précis of the American art scene from 1945 to 1975, which he predicts will go down in history ...

My own "The Triumph of Beauty" might be worth a read:

National Vanguard

The Triumph of Beauty

American Dissident Voices broadcast of January 30, 2016 https://nationalvanguard.org/audio/ADV%202016-0130sr.mp3 by Kevin Alfred Strom “YOU HAVE ...

Scott Burdick did an excellent video series titled "The Banishment of Beauty" which is very much worth watching:

"Scott Burdick" "banishment of… - Invidious