I've always felt the situation is a little two-fold. On one hand, Mike really does seem to think that every bit of honest criticism is "hating", or at least he comes off like that. We have no clue about exactly which reactions he is talking about, but he has also said that he takes things to heart too much, so by extension, he is also very likely to take honest criticism personally.
However, there is not a single community that's exempt from people who will criticize everything just because it's (in this case) Mike Portnoy doing it, even if their criticism is well-argumented. DTF also isn't exempt from it. And for people who know that Mike is often reading, and that he reacts as he does, we seem to phrase ourselves a little too harshly sometimes. In direct dialogue between two straight-talkin' individuals, it would all sound pretty good and proper and no offenses would be taken, but when someone like Mike (presumably is) reads it on the board, it can come off as "people on the internet ruining his day being out complaining" or whatever. We're not responsible for his reaction, but we shouldn't be surprised at it.
But yeah, just talking to bosk now, if a person runs a fan board for the passionate, internet-savvy, and large fanbase of your (now ex) band, and goes through a lot of difficulties, even forum splits, and manages to keep it all together, they deserve a little more than a casual thank you, let alone to be treated better than how you've said he's been treating you.