Now, disclaimer, age verification is itself evil and stupid. It sucks that we even have to think about "how to make it work". But if we live in a world where it exists, here is what I think is the only sensible way to go about it.

So it occurred to me that the critical vulnerability of standard age verification systems and the reason they are so unsafe is that they are all done through entirely digital methods. But the fact is, we have had safe and secure age verification for decades for buying alcohol. That is far far safer because the ID isn't stored anywhere, it is only seen by a real person. So here's my idea: an in-person retail location that sells inexpensive "access codes" of a sort. These codes give one-time access to the website for the IP address, after which the site stores the access as a cookie or associates it with an account the user is prompted to create. But the retailer selling the cards is required by law to ask for the customer's ID using the same procedures as we use for alcohol. In effect, you turn the retailer into the verifier, and the code is used as proof that the user is indeed over the required age. The ID stays safe and secure as it never comes into contact with a computer.

There are two main problems, both of which I think are somewhat workable. The first is that this would mean that access to any website needing verification is no longer free. I offer (with some reticence since I'm sure that others will vehemently disagree) that the anger a user feels from having something that was formerly free now costing a buck or 50 cents or whatever is substantially less severe than the anger that would come from the fundamentally unsafe and insecure methods of age verification commonly employed. Again, this sucks no matter what, but if age verification is a non-negotiable (and I don't think it is) then this is the best way to do it.

The other problem is logistical. There are thousands of websites needing codes, and billions of people wanting access. There are several options available for managing this huge demand. First of all, it's technically not necessary for the codes to be on physical cards in the way that gift cards or coupons are. A firm selling access could simply order a run of codes, on a physical sheet or a digital document, from the websites, whenever there is demand for them. Users seeking access to less in-demand websites would likely need to wait for the firm to have them delivered, as it's unlikely that the firm will have less-popular service codes on hand on a walk-in. For remote locations, a consumer could order codes on a firm's website. The salesperson would then travel directly to the user's door and check age there. Or you could have traveling salespeople.