A simple zero-knowledge credential system isn't sufficient. It would need to embed some kind of protections to limit how often it could be used, to detect usage of the same credential from multiple (implausibly far apart) IP addresses. There would need to be extremely sophisticated reputation scoring and blocklisting to quickly catch people who built fake identities or stole them. And even with every one of those protections, a lot of them will still be stolen and abused.
Yes, I wonder how feasible it is to do that while still protecting state of being anonymous.
And what if you develop this very sophisticated system of reputation score, what if bad actors find a way to still perfectly abuse it, e.g. they pay for desperate people for the IDs and then stay just within the limits ever so slightly.
Would you be able to easily iterate on the system when that happens to make it more secure?
But if you also track IP addresses then doesn't that already mean loss of anonymity?
And ultimately with something like IP address, a bad actor could offer you to download an app where they could simply use your IP address to post content/propaganda from under your ID and IP.
It would be more expensive for bad actors, but also I think there was period when Facebook accounts were bought and sold, and there was very active market for that. I imagine teenagers for example are really easily tricked into selling their creds etc.
Also Reddit and other social media accounts are being sold a lot, so definitely there would be market for that.
There are a lot of risks here and I think it’s very challenging to build something anonymous that can deal with (say) Google’s current level of fraudulent behavior, let alone what we’re likely to see in the future.
Regarding the IP address question, I’d assume you could decouple the IP address verification portions from the “know who the person is” portions with some clever multi-party computation. Someone always has to know your IP address, but it doesn’t have to be the same person you’re talking to. (Think of Tor as an inspiration here.)
