I think you mean mostly in the west..
i think it might just be an exoticism thing(?)
ive seen East Asian women date white guys who would probably be considered ltns/mtns by Western standards, but they genuinely find them attractive and give them Chad treatment jfll
and I think the same thing happens with East Asian men. there are so many western girls who are into korean dramas, kpop, anime, so an East Asian mtn guy can already fit into a certain fantasy or aesthetic they’re attracted to
so maybe it’s not necessarily that East Asians are objectively more attractive, but that people already have a positive image associated with them because of media and culture
add the novelty/exotic factor and I can definitely see why an average-looking person might get perceived as much more attractive..