I’m not sure about that. Novelists in particular ask for a lot of space in your head, and I don’t see why you should be obliged to give that space to someone who grosses you out. I came to feel that way about Martin Amis, Brian Herbert, Tom Clancy (et most of al) and Ayn Rand for example.
That said, I came to those conclusions from reading their books, not from off-page third-party smearage. Though, given the finite length of life, if some author were described as “the plain-speaking Ayn Rand of traditional family values” I’d probably decline to give them a try.
I never had the experience of meeting, say, Robert Anton Wilson or Iain Banks and finding out they were jerks in real life, so I don’t know how I’d respond to that. I don’t think I’d stop enjoying their work, but I guess I’d die a little inside, and if they were really awful I might make a point of shoplifting their books in future.
Anyway, I’m curious to know what’s so evil about John Scalzi. I tried one of his books (Old Man’s War) and wasn’t really into it, but I don’t remember picking up any gross vibes.