So the death of anonymity. I already hear the defenders of such a proposal: "If you don't want to give Facebook your federally issued ID then you still have the darkweb!" Followed by an endless stream of hit pieces equating everyone fleeing to non-privacy invasive platforms as nazis/pedos, and mobs of idiots demanding that infrastructure providers null-route wrong-thinkers.
Are you sure that really want a CAC? The OPM gave my biometrics and SSB to China, as well as every other military/gov employee. Except the CIA - the only one who managed to fight off the administrative record merge. If only they didn't draw so heavily from the veteran pool...