Bedrockgames
I post in the voice of Christopher Walken
Upset people like to complain. Happy people are usually content to be happy. Don't mistake a lot of complaints about this as indicating that it is anything other than a small minority of people who are bully DMs. Even if it is a bell curve, it's only those on the extreme end that are bad. The middle of the curve isn't the low end of average, and average spans a large part of the bell. I've encountered about as many truly great DMs as I have bad ones. There aren't that many of those, either.
I have to second this sentiment. while I have run into the occasional bad GM. For the most part, when I have encountered players who complain about this, it has been my observation they are often unhappy under just about any GM, and tend to just complain about lots of things in general. Or I see players who are overly rigid about the kind of GM they are happy to play with. Most players I know are pretty flexible and willing to engage a number of GM styles. I do think a lot of this has to do with attitude. If you go into a game looking for things to complain about, you will easily find them. I generally don't complain unless it rises to a certain level.