> just because you need your ID to buy a beer
You keep making this comparison, but it's not appropriate. The closest real-world analogy: in order to buy alcohol, you need to wear a tracking bracelet at all times, and be identified at every store you enter, even you you choose to purchase nothing. If our automated systems can't identify you with certainty, you'll be limited to only being able to do things a child could do.
And the real world has a huge gap between a child and an adult. If an 8-year old walked into Home Depot and bought a circular saw, there's no law against it, but the store might have questions. If a 14-year old did it, you might get a different result. At 17, they'd almost certainly let you.
The real world has people that are observing things and using judgement. Submitting to automated age checks online is not that.