> Tying artistic and financial success [...]

If you're referring to the article's description of the study's measure of success, the metrics had little to nothing to do with direct financial gain.

> [...] in the sense that they have vanishing influence on public discourse.

Nothing inherently requires art to be a part of the public discourse. Sometimes artists create art for art's sake, and/or just to make a buck. Sure, occasionally some art makes it big in the public eye and becomes part of the zeitgeist, but the vast majority of art barely sees the light of day.