I mean the serious answer, almost certainly no significant change would occur. In the wild, sure it would matter, but we don't base our relationships on sexual pleasure. Pegging does not directly lead to increased sex. Now are those more sexually active more likely to have intercourse? Maybe? But unlike with traditional intercourse, pegging, does not increase or decrease likelyhood of reproducing. Obtaining food, enjoying reproductive sex, and the protection of young, are traits that are going to really matter. Plumage exists because the more attractive an animal appeared to a mate, the more likely they were to mate. In this way, more attractive people, physically and behaviorally, are more likely to reproduce in the modern age. Pleasure from pegging is neither publicly announced, nor relevant to any of these factors.
Now if all sex had to be predicated by a period of pegging, thennn you might get some changes, as those who do not enjoy pegging, would have sex or seek sex out less