Interesting thread, which could be expanded by going in greater detail by describing the strange fauna that dwells in the off-topic region.
Unfortunately, Mr. OP made an unforgivable omission: he forgot a very important item in his list, one that could hardly be described as a stereotype, given its uniqueness, but whose abscence is both striking and shameful.
Me.
Of course, neither "me" nor "Argonautidae" are very catchy labels.
I suggest "Pretentious Egomaniac" instead.
is there a person who only plays speed chess,
or the people who absolutely hates speed chess?