Many users do not desire to interact with underage users for many reasons. Some underage users may wish to opt out of seeing 18+ users so they may bond with people closer to them in age or perhaps for safety. I think a functionality to
- mark your account as 18+
- hide content from accounts who didn’t mark self as 18+
- hide content from accounts who marked self as 18+ would be very useful to those users and set a higher standard of personalized experience for users engaging with social media.
As said by others creating a giant community of under age kids where anyone could just claim to be under 18 is a bad idea but also any kid could just claim to be born in 1942 like I did when I was a kid