Yeah...I'm fully aware what a ZKP is..you're just missing the point.
> You then still need a trusted ID service or algorithm to capture an image of the user _at the time of use_ to compare that to.
> Just having access to your digital ID credentials proves nothing
If I have access to your digital ID I shouldn't be able to impersonate you anymore than I should be able to fly using your passport.
Your passport is useful not just because it's difficult to forge, but because border control is a thing.
If you steal my passport and I' don't signal it to the authority, you'll be able to sell it on the black market to someone looking approximately like me who will subsequently be able to use it to impersonate me (it actually happened to a cousin of mine).
Why do you require digital ids to have a higher security standard than an actual passport?
(Some countries like the US mandate biometry in passports, but you could add that to your credit card as well, there's no technical limitation here even though it's probably too expensive for too little benefits)
Some people may be able to fraud by stealing and reselling digital ids, but it's not a fatal issue if it's not a fatal issue for a passport. Again, the optimal amount of fraud is non-zero.