There's a lot of it about
Over the years, I have come to see a pattern. The people who write code are good at communicating with computers, not so good at communicating with people. In the past, somebody with some skill at writing could produce an "unofficial" manual that usually managed to be well-organised documentation. Now we told to look it up on the web, and watch YouTube videos.
I don't really expect Linus to be subtle, and he is likely dealing with too many people for who subtlety is a waste of time. What I see of this "bad language" is more about intensification than insult, driving the point home.
He doesn't know all the tricks. He doesn't use dramatic irony, metaphor, pathos, puns, parody, litotes or satire.
Just using good English should be enough, but have you seen any recent documentation?