All anyone cares about is covering their own ass, so it'd solve that issue, but it would have neglibile effect on anything real.
Source: Used the internet when I had to lie to every site about being over 13, so lied to every site about being over 13. Also vrchat requires being 13+, and boy, does 'requiring' it not accomplish anything at all.
I get its just trying to shift the burden onto the parents and the "lying child" but at the end of the day it just seems like it would collectively waste so many hours.
IMO, I just feel like it wastes too much time to justify itself. Hundreds of thousands of hours spent on a solution that relies entirely on the (unreliable) respondent.
Yes, we all know kids lie when they see the age verification, but the presence of age verification moves the liability away from the developer/publisher and onto the parents/guardian of the underage kid.
Obligatory IANAL.
Or you use the social graph to infer age: somebody who mainly plays with 10 year olds is probably also about 10. If they claim to be 20, require an id anyway.
Non-gaming companies deal with this all the time. It's annoying, but shouldn't require blazing any new trails.