As the power dynamics of relationships becomes more equal… woman are already earning more college degrees than men, have already surpassed men in several professions, and more and more woman out-earn their husband or boyfriend… in the very near future, almost every woman will own a strap-on, and will regularly fuck her husband or boyfriend with it. The current taboo associated with a heterosexual man taking it up the ass will dissipate, and it will just become a very normal part of his experience.
The same thing goes for cuckolding. As the dynamics change, and women begin to assert their authority within the relationship, it will become more and more common for women to occasionally seek sexual satisfaction with other men, while otherwise remaining loyal and married to her primary partner. This will particularly be the case regarding women who are married to men with smallish endowments and mediocre sexual talents. This too, in the very near future, will just become a very normal aspect of marriage.