More likely that the person complaining about a social problem
is actually trying to make the project worse. Like e.g. outsiders coming out of the woodwork to push CoCs on projects that don't have them.
> so all we have to do is ban the person who said that <prominent contributor> groped them at a conference and we can get back to work
Yes. Such an issue should be brought to the police, not be posted on an issue tracker for rallying social media lynch mobs. Cases of exaggerating or straight up lying about sexual harassment in order to remove or destroy someone are common enough, and consequences of a mistaken judgement severe, so the presumption of innocence is very important.