Whether or not the term was a joke, the point stands. While anime had been big since the 1990s in the US, it would not be until 2006 with the series "Happiness" for an anime character like that to get popular with US fans [indeed, Jun and Bridget were the reason the trap joke was coined]- and it wouldn't be until the 2010s when that character archetype became commonplace enough you could expect at least one or two traps to be running around a seasonal anime, which as we established coincides with when the autist to trans pipeline started.