It's not quite as one sided as you put it, either. The most recent last minute feature was pushed for rc3, and wasn't big filled. It was also a feature that enhanced stability, which is the reason Kent submitted it there. I'm not saying he's right, but it's important context here. And he's far from the only one who has done this. Someone recently added new hardware support in rc7.
Also, he has improved somewhat. Arguably not as much as he should, but things aren't as bad as they originally were.
And as to the attitude - he's in good company, honestly. Especially in regard to Linus, them judging Kent is like a group of lepers judging a beauty contest. That's the point this article makes very well.
None of this excuses his behaviour, but it is important to put it into context.