Linus is abrasive, but he usually has a good explanation for why the target of his ire is a moron, e.g. everytime some coder without Linus’ experience suggests converting the kernel codebase to C++.
Let’s be honest, most developers are average at best, and knowledge is our status play. Scoring points against Linus’ decisions are one way to get you noticed, which makes him a target. If I had to deal with that shit everyday, I would do my best to discourage point scorers by putting them in their place as well.