Men wear makeup in South Korea. Men in the u.s. do lots of other things to increase their attractiveness (dye their hair, get vanity muscles, haircuts, clothes). Yet it remains taboo. Who knows? Ask women.
Presumably you're asking this question because you wish to profit from the insight and not look fabulous on a Saturday night. IMHOs men's makeup will always be a small market compared to women's and because of this, the only way to make money is to find a men's makeup startup.