the man is a predator. 
Not my hill to die on and as I've said, the guy's a fuckin' tool... BUT... the new normal of an accusation and guilty until proven innocent is a bunch of shit. 
 i hear ya.  if this was one accuser, then i'm with ya.  but when a bunch of women come forth (not an easy thing to do, especially with this douche who has an online army), AND it fits a pattern, i'm admittedly pretty quick to believe the accusers.
Portnoy didn't force some IG sloooot to get on a flight, go accross the country, and stay at his home. 
 that still didn't give him permission to abuse these women.  what's next - the way in which she was dressed was just asking for it?
per the stories, there was a (criminal?) lack of consent.  he taped sex acts without asking.  he did extreme kinky shit (choking, spitting, etc.) with a first time partner (essentially a stranger) without talking about it first.  ladies said stop, he didn't (aka rape).
agreed that he has not yet been convicted in a court of law.  considering the likelihood of abusers getting jail time for their actions, i think that sometimes we need to get ahead of this type of behavior.  if dude gets a bad reputation as his likely only punishment... well, let's hit him with something.