First, if I were a minor and had even a compulsion to enter Wolfery regardless, it would take me less than 5 minutes to fake my ID in one of many ways I can imagine.
Second, I’m sure even a blurry image of my ID could be enough to doxx me. Your proposal involves creating a database of personal information, and not only it can lead to some legal issues, it will be hacked and used by malicious third party.
Third, I can imagine adding this extra step leading to massive drop in playerbase among legal adults, especially new players that don’t yet see this site worth that much effort and sharing their information.
Your intentions with this idea are good, but it simply won’t work as you suggest. It will only be an obstacle to real adults, while minors would find it extremely easy to bypass.
Unfortunately, the only real option is to trust the site users’ honesty and reasonability.