Not being a misogynistic isn’t “moral purity” it’s the minimum standard of decency. And nobody is saying Taibbi hasn’t had notable achievements. I’m saying I have no interest in seeing someone like him do an AMA on HN. And as an audience member, I certainly don’t want my friends knowing I have an account and post to a site that’d let someone like Taibbi do an AMA. He can go be notable somewhere else.
Sure, but if we judge everyone by their worst actions I'm sure we can implicate a large swath of people who have ever achieved anything. I find Taibbi's work interesting and I would prefer not to deplatform people for actions unrelated to their work. We have a court system for punishing people. While I think it's entirely reasonable not to support someone or their work on moral grounds I would prefer others not to make that decision for me.