Earlier quoted context omitted.
>Basically when people stopped only drawing religious art and portraits of nobles. We drew vastly more art. The kind you describe was just more likely to be preserved as the institutions they were on about and the buildings they resided in persisted.
Surely people created a lot more art, but you're eliding the dynamic of professionalism. Art is ludicrously labor-intensive and so the vast majority of professional art (i.e. most art worth saving) would have been done for rich people.
It just so happens that a lot of the modern/contemporary art talked about is mostly the domain of professional art (and examples that say otherwise are often not even thought of as such like hippy tie dye clothing.)