But in most cases, it is, because most adults are not that technically inclined to get around the logins. Sure there are some tech savvy ones who will bypass it. And maybe a few kids who will use their parents' accounts rather than just bypassing the logins but it's still the family accessing the information, but for the majority, it does work as a registry. And though it's only on a few categories of sites now, the categories inevitably will expand. It's not just porn, but info on reproductive and gender healthcare, LGBTQ+ dating, and many other subjects that "children must me protected from", but really they want to know who's gay, looking for abortions or transgender healthcare or information about whatever other rights their government is trying to force them to give up.

Which they, as the governments, can choose to legally treat as the same thing. "You are guilty of whatever someone does with your account" is not a new concept, it's just one that most places have chosen to reject. It can always be overridden, such as for the Palestine Exception.