Well it's an aggregate. Advertisers don't want to spend money on a platform that allowed Russel Brand to make money. The problem with advertiser's and the public is that platforms are seen as whole. Advertising on the platform is seen as a vague approval of the platform as a whole.

There are plenty of rappers monetizing their videos. King Von was never demonetized despite being known to have killed at least 7 people. That is much worse than what Brand is alleged to have done. So this isn't a moral judgement, this is a business decision.