"Art rock" can sometimes be a derogatory term (i.e. "art not rock").

Any genre I can think of has had adherents who explored a more "theoretical" side:

John Fahey (art blues?)

The Incredible String Band (art folk?)

Rhiannon Giddens (art roots?)

May I add to your list of art rock The Bonzo Dog Band (who frequently allude to Dada and other art / literary movements)? https://youtu.be/OelZyzXZBHk