Wow, that thread title smelled like flamebait initially, good rescue with the actual post OP, but it was a close call
Personally, I can understand that an attitude like the one described by the OP can be very frustrating, but my two cents are: I do not see a difference in gaming abilities based on gender, meaning I think, yes, girls can be good gamers.
Do I think most girls are merely average gamers? Well, yes, because I think so about the guys as well. Most of the gamers are mediocre at best (which empirically should be kinda "duh"
, so the group of gaming women should contain plenty of mediocre gamers,
exactly the same as the group of gaming men.
I think there might be statistical differences based on preferred game types/genres and skewed because of the differing number of female to male "core" gamers (or at least the ones you typically find online), but that would be an entirely different (and pretty long discussion) and those do not change my personal belief that yes, girls can be good gamers with at least the same potential for gaming greatness as guys.