True but to move towards a more decentralized approach we definitely need a layer to protect our identities so the commenter's opinions are not influenced by the person behind the account but by content posted by the account. Ad Hominem attack for instance: It's problematic because it avoids engaging with the actual argument and diverts the discussion to irrelevant personal attributes.
The forum is not decentralized and there is no way we can move towards that in this very forum. If what you proposed is possible without all of the drawbacks, then it would be very interesting, but the drawbacks are inevitable IMO. I don't know why some users have a problem when people create alt accounts just to say something they don't want associated to their "real" usernames, i think that is the best approach for "unbiased discussion".