Vanilla is a product of Lussumo:
Documentation and Support.
I don't see why a person wouldn't self-identify as a "gamer" or why that would be ridiculed
I don't think gamer necessarily carries the connotations of "loners, overweight, unclean and antisocial" although YMMV.But it does, that's the thing. And not just video games, but wargaming, card games, pen-and-paper RPGs, LARP, and so on.
This is the thing about the "gamer" stereotype: it only focuses on the people that do it constantly, to excess, to the exclusion of all else.