And the worse are often those that brag about how "open to criticism" they are.

It's a trap for literally-minded/low-EQ people.

There are those that are indeed open to criticism, but those are almost never the one's that are gonna tell you about how open they are. Rather they are the ones that will actively engage in such discussions and technical arguments with you, and even enjoy it. You wont be "invited to criticize" them, you will be criticizing stuff and arguing together all the time, as if you're peers.