Yes. I’m not saying that they wouldn’t try to come up with bogus/farfetched regulations, but they legitimately cannot do anything about what goes on behind closed doors in someone’s house. To do otherwise would be a breach in that person’s right to privacy. It’d be like an HOA telling you, you have to vacuum/sweep/mop every other day, otherwise you can be fined. (or saying you can’t have sex on Sundays)
HOAs do have some extralegal clout, but the right to privacy stops them from interfering in anything you do that isn’t openly visible. (i.e. Doing a meatspin in front of a window facing the street can be penalized, but taking a dump in your kitchen sink can’t, unless the sink is in front of a window facing the street and the blinds/curtains/shutters are open.)