[riverlong]

I think there's a solution in pseudonymity: it has the liberating effects of anonymity, while providing some accountability that there's a real human behind the digital face.

For example, suppose there's some repository of hashes of Personal IDs. If you want to sign up somewhere, you have to submit a Personal ID that corresponds to such a hash -- the Personal ID doesn't get stored anywhere, but it authenticates that you're a real human. (Obviously this is a naive solution and something more clever would be necessary, but it's just an example.)