It uses a one drop rule to test websites. Once theres a teensy bit of adult content, and as has been pointed out this covers things like googles unsafe search modes, then the requirement is to block first and ask questions later.
Requiring people to be licensed or verified to access content is as much censorship as blocking it entirely. There are valid reasons to not want to be on a conservative governments list of porn users. You need to expose yourself to risk to access content? Censorship.