The parable of the boy crying wolf is not about lies but about desensitizing your audience to what you are saying. I've read enough of the rants to know there is very little signal to all the noise he makes.
The grsecurity stuff could be bad but I sure as hell am not gonna get my analysis from Linus. If he acted more like a grown up then maybe but he doesn't. He character assassinates and then says you are doing silly pointer arithmetic. Can just mention the pointer stuff without shouting and screaming at author of the patch.
The drama in kernel dev is a direct result of his abrasive approach. He screams and shouts so grsecurity screams and shouts. Everyone else loses. The kernel dev space needs less drama and more grown ups.