You have a point. Though I suspect that average parents are either too lazy or not tech literate enough.

I do want to note that this California law alone doesn't say anything about content restriction. I won't be surprised if there was/will be another bill to assign the responsibility (which may be more controversial). But the current law is only about the age gating mechanism. And on the positive side it removes the need for actual age verification (like using ID) which other regions still insist on.