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: https://nationalvanguard.org/2015/02/berg-berg-and-berg/

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

https://nationalvanguard.org/2016/01/the-triumph-of-beauty/

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

https://invidious.tiekoetter.com/search?q=%22Scott+Burdick%22+%22banishment+of+beauty%22