And here's a timely article by @mgeist about The Legal and Privacy Concerns of Mandatory Age Verification Technologies. It focus on Canadian legislation, but the risks and harms it discusses are applicable everywhere.

"A harm that proponents of these technologies want to mitigate is “the extent of youths’ exposure to sexually explicit material online, the frequency with which this material is of an aggressive or violent nature, and the potential harms to body image or mental health it may cause”. Opponents note that these technologies are harmful in that they would limit young people’s (especially those from marginalized groups) “access to online content or forums” that provide “avenues for community-building, civic engagement, and education”, as well as “self-discovery”. Further, use of such technologies comes with risk of data breaches that would publicly expose people’s online activities, consequently causing “psychological or physical harms” and possibly discouraging them from “operating freely in the digital environment”"

https://www.michaelgeist.ca/2025/07/risky-business-the-legal-and-privacy-concerns-of-mandatory-age-verification-technologies/