I'm not sure that it would be too hard technically... basically, auth+social-network. Basically Facebook auth without the rest of facebook, adding attestation.

IE: you use this network as your auth provider, you get the user's real name, handle, network id as well as the id's (only id's not extra info) of first-third level connections.

The user is incentivized to connect (only) people that they know in person, and this forms a layer of trust. Downstream reports can break a branch or have network effect upstream. By connecting an account to another account, you attest that "this is a real person, that I have met in real life." Using a bot for anything associate with the account is forbidden, with exception to explicit API access to downstream services defined by those services.

I think it could work, but you'd have to charge a modest, but not overbearing fee to use the auth provider... say $100/site/year for an app to use this for user authentication.

I don't think the main challenge is building this system, the main challenge is getting enough people using it to make it worthwhile.

Personally I think it should be a government provided service, not something with a sign up fee. There's actually no point at all in building this if people have to pay to use it, because they won't