The art theory is interesting, but incomplete. It seems that once photography was invented, the art world needed to move towards art that was generally not highly visually appealing, because verisimilitude was too cheap. Note that art having mass appeal is often taken as a bad thing. If everyone likes a piece of art, owning it says nothing about you. If no one likes a piece of art, and you pay a lot for it, that does signal something about you. Basically, the upper class and the artistic cognoscenti had to aim for something that did not have obvious appeal and that made it easy to regulate the entry of new artists, and modern/post-modern art accomplishes that perfectly.

A similar phenomenon likely occurs with wine. There are many drinks that taste better, but what's the point of drinking root beer if everyone likes root beer? Wine has high variance in flavor and does not taste good enough for people to like it without putting in serious effort. It's the perfect status-signaling drink.