If you are too open-minded... your brain might fall out. ;o)
On the other hand, people more often have the opposite problem... too proud of themselves and their ideas. People should lighten up. I'm trying to not take myself so seriously.
Trouble is the pool of people at these websites are fairly bright, driven to excellence, competitive and opinionated. This combination of traits has made many of these folks the best in their trades. They want to be the best and build the best.
Instead of checking egos at the tavern door, the gloves come off.
The net lets people make inflammatory remarks like an uninhibited drinker at a bar, without fear of being punched out... then add moderators asleep at the wheel... only waking up as the car hits the rumble strips on the shoulder and overcorrecting... it gets nothing but ugly.