What needs to be kept in check is the scope. Let's say they try to age restrict sites that are subversive, but not obscene. That's what I'm talking about.
"Children shouldn't view pornography" is fine as an overall goal. A law that suggest the content providers track the faces and passport details of all users is a ridiculous way to fail to prevent that however.
It is however a great way to have an readily accessible log of exactly which citizens are viewing content the government finds questionable.