I get if you don't feel it yourself but it's weird that you don't understand it. People generally like when people treat other people well and act in a generally moral way. A public figure who cheats on their spouse (and not some open marriage kind of way) goes against that, so people get upset. Oh, fine, whatever, I get it and think it's stupid how is it stupid? do you not judge people for other shitty ways they might treat people poorly and inflict emotional harm on them? i am obviously much less bothered by his infidelity than by the possibility that he physically harmed her in some way, but there's no question that it is a shitty thing to do and makes him a shitty person.