Historically, artists were independently wealthy (as were early scientists) or they lived off the patronage of the wealthy. Intellectual property and copyright laws allowed art to be a viable commercial venture without direct patronage.
Well, no, I mean if you want to get specific, IP and copyright (copyright specifically) created a structure for government to register and track written output. Our current conception of "the artist" is relatively new, and patronage models/gift economies strike me as...well, still pretty relevant despite IP. People seem to be focusing on the Artist and not the artist's intermediaries (publishers, for instance) and that IP was also meant to protect and promote industry, for which it has been successful (maybe too much).
I mean a good thought experiment here would be to replace "artists" with "entrepreneurs" or "founders" ("historically, [...] were independently wealthy" would expose some of the myths we attach to the idea of "self-made" which we rarely attach to artists and authors) here and rethink the history of Western commerce from that perspective.
The US has cultural poverty because it has decided to support litigation machines.