Women experimenting with their sexuality is more accepted than it is for men probably because there’s no penis involved so no party is penetrating the other which is seen as a dominant/ submissive act. It’s also kind of considered just a phase all women go through so they’re not really seen as gay. It’s also socially encouraged for men to have multiple sexual parters while it’s frowned upon for women so a guy having a threesome with two women is celebrated for his prowess while a woman having sex with two guys is seen as a used up whore. All of this culminates in the idea of girl on girl being hot and a common male fantasy where’s guy on guy is just seen as dirty and gross.

I don’t hold any of these views myself just explaining my understanding this is all about double standards in sexuality and women being treated as commodities rather than the human beings they are.