Age-verification systems vary greatly in complexity. For instance, a pop up that asks you whether you’re under 18 collects no personally identifiable information and also helps defend websites against legal repercussions. On the other hand, more robust systems usually require more decisive proof, such as a photo of your driver’s license or passport.
Even if this data isn’t stored or shared with other organizations, there’s always a risk. For instance, the system could be hacked or one of the employees responsible for verification could simply leak your information. The company that provides the age-verification service could even be bought over by someone with less noble intentions at a later date.
As such, while it’s understandable to want to protect young people from adult content, requiring users to upload their ID (which may reveal their home address, date of birth, and full name, all of which can be used by identity thieves) is not the way to go.