The problem with infinite, easy to create identities leads to a well researched attack, known as a Sybil[1] attack.
If there isn't some type of cost or friction to creating identities, you will have a lot of bad behavior, full stop. This has been shown time and time again, so it's basically a non-starter. I don't want to be part of any social network that has this feature (infinite identities), its going to eventually turn to shit or require intense moderation (or both!)
I think this is true if the system is global or there’s model where Sybil resistance is “here everyone, have an access to write to the database”. In a system like HN there’s value in Sybil resistance. On your Twitter feed, almost none.
So I disagree this is a non-starter, because we didn’t find a solution in the past, but rather an ideal place to start and a great space to discover new Sybil resistance mechanisms (which we have over the recent years).
Domain based identity also enables attestation which could be use to artificially add even more friction. Plus, since it's not constrained to a single platform, you could have 3rd parties that assess trust and reputation.
If there isn't some type of cost or friction to creating identities, you will have a lot of bad behavior, full stop. This has been shown time and time again, so it's basically a non-starter. I don't want to be part of any social network that has this feature (infinite identities), its going to eventually turn to shit or require intense moderation (or both!)
1. https://en.wikipedia.org/wiki/Sybil_attack