> We do not have to convince the population. We have to convince regulators and if it becomes necessary the EU/national-level courts that handle human rights violations.

Without the population on your side, it's some insignificant minority's words vs. corporation's power determining where the lines get drawn by regulators. The people can put a leash on politicians who cave too hard to corporations by voting them out of office, but if they don't even understand the issue and have been conditioned to accept age verification, that will never happen.

> One of the large issues though is that the reference implementation relies on Google Play Integrity for device attestation (+ the iOS counterpart)

I am confused as to why you suggest my view is US-centric, and then go on to acknowledge that the EU is currently in the midst of rolling out regulation that de facto enshrines the Google+Apple duopoly in law. The EU bureacracy seems to be just as captured by corporate interests as the US. At times, they put up a token protest against Apple/Google, but generally only insofar as to promote competing European corporate interests where applicable. The EU would certainly prefer to serve European corporations over American ones, but the European people don't seem to factor into the equation at any point.

the EU is currently in the midst of rolling out regulation that de facto enshrines the Google+Apple duopoly in law

It isn't, it's not enshrined in law, de facto does a lot of work here. IANAL, but I'm pretty sure such a requirement will not hold up in court either. Besides that, the developers of the reference app have stated that national apps do not have to require strong integrity from Google Play Integrity. It seems like they took the standard platform path either because they did not have time the time or knowledge to do anything else.

At any rate, I'm optimistic that it won't require passing strong integrity in my country. Age verification will be added to our national ID app (DigiD), which does not require passing strong integrity, even if it is used for more security-critical applications than age attestation.