There's a difference between disrespect and criticism. Stating you feel someone is a bad writer/artist based off previous work isn't disrespect.
If a writer or artist worked on 9 titles, and you disliked 9 of them, it's a safe assumption you'll dislike their next one. If the series is good, I'll be the first to admit I was wrong. But based on previous history it's "outlook not so good."
Last I checked, forums were meant for discussion. Someone posting a different opinion than yours isn't bitching.
It's almost as if the internet is full of multiple people with different opinions posting in one spot. Crazy.