Bias has nothing to do with it, it’s applying probability. Saying that because there are multiple accusers make it more likely that he is guilty than that there is a malicious campaign against him isn’t controversial.
You understand there’s a difference between assessing guilt from a legal standpoint and forming a view on culpability based on likelihood. Or maybe you don’t?
It’s not unreasonable to conclude that it’s more likely that he’s a rapist than not. That doesn’t amount to a certainty, but it’s like seeing overcast skies and saying it’s likely it will rain