Comment by Mashimo

Well for one they did not have access to 4k 60 fps incest porn at a moments notice in your pocket.

You had to go to a special store where an adult checked your age.

But I guess the better option would be to give parents the propper tools. For example every OS could have the option to set up a child account, that gives the age range to the app store / website the user visits. And the app store owner and website owner (of a certain size? Not sure) have to implement it. Just like store owners can't sell alcohol or porn mags to underage customers.