I have pretty good smell, like I can sometimes follow a person's scent trail, can tell who are related, smell cooking in neighbors houses, etc.

I suspect we would decide that farts are socially acceptable. Lots more people sneak farts than you'd think, and you just get used to it. Calling it out is crass and childish. Same with bad breath, general BO, skin, stuff on shoes. But also mold and yeast in places you wouldn't suspect. We'd instantly ban all scented soaps, dishwasher detergents, and especially dryer sheets, those smell awful.

I definitely have a higher tolerance for natural smells but much lower tolerance for synthetic smells from the average person.