But there are lots of other companies that are successful where people don't act like jackasses. For example, Google culture is anti-jackass, Googley means not being a dickhead. If you have a problem, explain what's wrong calmly and coherently, it's more efficient. Simply telling someone that they, or their code, is a piece of shit is not likely to be as efficient.
IBM is another, when I worked at T.J. Watson, people were very civil.
Civility is not about being "fake" or "politically correct", it's about being able to communicate your position by reason instead of by emotion, by shouting, by abuse, by reptilian brain.
Linus gets a lot of leeway because of his work on Linux, and we will forever be thankful for that. But I don't believe good works earns you a pass from criticism of behavior. The founders of the United States are forever thanked for the Constitution, but that doesn't let them off for being slaveholders.
I expect there will be some reflexive downvoting on this for criticizing the prophet, but honestly, Linus makes geeks look bad socially. Say what you will about Richard Stallman, there are lots of things he says I disagree with, but he says them with integrity and positivism and love, and not with angry denouncements.