They do, don’t they? Apple devices have had a robust whitelisting/blacklisting feature for at least a couple of years. I use it to block websites and apps to lessen my phone addiction. I’m sure Android offers similar features

Block -> opt out

Allow -> opt in

And a techie customizing it is v. different than turnkey for parents.

But yeah! Same principle, that's why I'm sure it's been done / will be done.