Why is cheating in relationships by women more normalised than cheating by men ?

Like how it's 'accepted' that women can date/flirt/sex other women and basically nobody bats an eyelid anymore, it seems women cheating in relationships is going down the same path - basically being 'normalised'.

But if men try to date/flirt/sex other women, or cheat in relationships, the entire femininst movement of the world tries to inflict a Sandy Clam pincer movement.