But his behaviour isn't new nor is it surprising.
Also: choosing not to work with someone is one thing. But should these organisations remove all mention of their previous association? Either Zak S deserved to be in the credits because of the work he performed for WotC or he didn't. It'd be like removing Kevin Spacey from the credits of all movies he's ever appeared in.
Well, it wouldn't for a variety reasons. Two of which that spring immediately to mind are contractual agreements with the Screen Actors' Guild, and the (perhaps odd) ways that intellectual property can be owned by your employer. I know many people who can't even work on a potentially profitable project in the garage on weekends without their employer having the right to confiscate it. I don't know what contractual relationship Zak had with WotC, but I would not be surprised his contract didn't make his thought on 5e WotC property the moment he had them. (I'm not defending such nonsense, but there it seems to be the way the law works.)
Either Zak S was a known abuser and the industry has done nothing. Or a facebook post accompanied by no evidence is all that's required to have someone removed from the biggest seller of online RPG products. Either way I think OneBookshelf and WotC need to set some guidelines as to who they will and won't do business with and why they're only setting those guidelines now. Or else we're going to have innocent people thrown out of the industry at the whims of these organisations.
hmmm...I think you're leaving out the possibility of Zak being an "unknown abuser". That is, it seems that a lot of folks who knew him (I don't, I'm only going by the posts I've seen) didn't have a high opinion of his personality. So, they might think something along the lines of "Well, that guy is a jerk, but he seems to do good work (or has a big following, or whatever), and I don't really know that he's done anything all that terrible." That is, give him the benefit of the doubt (perhaps this is another odd American cultural trait). At least until something happens that either makes it obvious that he is as terrible as you suspected or that further association with him will damage your brand (regardless of your belief in the accusations).*
The only problem with those guidelines your suggesting is that its like asking someone if they are Chaotic Evil. "Are you a rapist?" - "No I was acquitted on all 27 charges." Alternatively, you could have some kind of "reputation protection" clause, like the NFL and NASCAR have for their participants. However, those have their own foibles, because reputation is a rather curious beast and subject to some rather fickle interpretation. (The NFL, in particular is noted for its rather odd and inconsistent interpretations of what will and will not harm its reputation.)
*Which is decidedly not to say that I think a corporation wouldn't happily let a vile person make them money until it hurts their reputation somehow, and then disingenuously claim ignorance. I would be surprised if that isn't the norm, in fact. I just think its not quite as binary as you're putting it.
