Surprisingly not that much. It happens, sure, but rarely. Most of the people that post there seem pretty aware of their position in aviation and generally are realistic about what they know. But, like I said, crap like that does happen...for instance I got heavily downvoted once for stating that I haven't carried an A/FD with me for a few years now...as an airline pilot.
You will also see the occasional question from a layperson wondering why something happened on their flight, or how to prepare for a flight overseas, or how to overcome airsickness. That kind of stuff. Also doesn't happen very often, though.
It does have it's problems...and here are some examples. There is an almost crippling level of hyper safety that prevails there. . Also they need to cool it with the religious devotion they seem to have for QT Halos. And lastly the deluge of flair updates and "I soloed today!" posts can get out of hand. And making all of it's faults that much more insufferable is the fact that the "reddit circlejerk" is very much in effect on that sub.