I have Harley Hahn's Unix book (2009 edition I think). In it, he describes some of the reasons Linux grew so quickly. One of them is that "Linus has a pleasing personality... in person or online, Linus pretty much gets along with everyone because he is so easygoing. As he once observed in an interview, 'Unlike Richard Stallman, I really don't have a message.'"

This part struck me - as a college student who hasn't been involved in tech culture for that long, all I had heard of Linus is about his brilliance but his harshness and perhaps arrogance.

So, assuming my impression and Hahn's are both accurate - what changed? I think that the stress of life gets to us and we start to cut the pleasantries, tact, and niceties that seem to slow us down. We don't mean to be a jerk, but the fast-paced lives we commit ourselves to don't allow time for us to treat others as respectfully as we can. We're blunt because it is easier on us and we don't care about what it does to others.