These discussions remind me so much of the US discussions about federal ID documents as verification.

There's a vocal portion of people which opposes any solution because "privacy, government overreach, surveillance ...". So instead of a solution like e.g. zero-proof age verification, that tries to minimize intrusions on privacy, the result is the worst of all worlds, maximum surveillance (but I guess it's ok if it is not the federal government, but meta), with minimum utility. Just look at the freaking mess that is trying to proof your identity in the US.

this position assumes the surveillance state or megacorps would be satisfied with a zero knowledge proof based ID/age verification system, which is not at all obvious to me

meta could spend their billions lobbying for that, if they wanted to

edit: to be clear, I do think a government developed and maintained ZKP ID/age system is the best possible compromise, I just don't think we have any chance of getting it

It's a bait and switch that can be seen by even Ray Charles from a mile away. ZKP assurances is just part of the high-IQ "useful idiots" spreading buy in for the bait.