IRL, I agree. But I'm asking about it as a decision in game design. What is the gameplay benefit to allowing your player to potentially screw up their relationship in some ways but not others? If it's the severity of the action, convey that in the value of the variable hit the player takes by doing it. But telling the player "you can be unfaithful here and here, but not here and here" is silly as a gameplay mechanic.
And if the difference between a blowjob and ass grabbing is too severe to lump together, consider that (according to the poster I originally quoted) you can make out with Riona in the theatre, but you can't kiss her on your bed. Even if it's based on severity of action, that still doesn't add up.
But MC doesn't know how dangerous either of them are. Oscar could be an amateur MMA fighter; Vinny could be a fake tough guy. MC certainly didn't know Vinny was armed. This is why I'm saying it doesn't make sense to gatekeep some choices but not other equivalent ones. If your MC had to have shown violent tendencies to punch either man, that's fine and makes sense. Requiring it for one fight and not the other, based on the severity of the interaction (which the MC can't possible know) is, again, silly as a gameplay mechanic.
The dialogue is different, but not by much. She'll take you home with her either way if that's what you want.
