A lot of these age verifications things have to do with "protecting children". If that's the end goal we don't really need to verify anyone's age. Apple/Google, any smart phone maker, should be forced to add proper parental controls.
Parents should be able to control what apps can be used, what websites can be viewed, who the phone is able to contact.
That doesn't require knowing my age, or anyone else's.
Also, as an iOS developer, it's not my job to parent your child. The age ratings are clear on the app store, if you give your child unrestricted access to a phone that's on you, not me. If the OS doesn't have proper controls that's on Apple/Android, again, not my fault and not something I should be forced to police.
Thanks to Texas, I can see roughly how old your kid is. I'm not supposed to keep that information though. ;) I'm sure everyone who makes app will comply with that and not use that information for any other purposes and you can bet Texas has the means to audit every app on the app store to make sure that they're complying. lol