Platforms like Spotify, YouTube, etc, are a marketing channel - not a revenue channel. They can be used effectively to develop an audience, but not to monetize it. For example see Pusheen the cat. Started off as a tumblr web comic/character and now generates millions in merchandising revenue: https://www.ndtv.com/world-news/how-an-internet-cat-craze-be...
I'd agree on YouTube however, artists I work with see very little income from YouTube, which is quite sickening and problematic for artists given how much of the younger demographic use YouTube as a primary source of music.