Sure, and lock your door when you leave home, that’s common sense. But it is not a reason to argue against outlawing burglary. I am not against taking precautions, though no precautions are foolproof and I have been mugged on a bus in bright daylight.
But I am against this edgy cynical idea that there is no point deciding rules because someone will circumvent them. Or that you are a naive idealist if you want better. Instead, what we do is we punish burglary, and it becomes rarer and rarer, and everyone lives better, even if one day you happen to forget to lock your door. Same thing for PII, and personal data in general. We should punish companies that are reckless with their data, and strictly limit the information access providers can log. This is not magical thinking, and is completely uncontroversial for medical or financial information. So why the phone cynicism (not from you, but from a large number of technophiles who ought to know better)?