Okay, but what is accountability? I would argue that accountability is a social/cultural phenomenon, not a property of the entity itself. In other words, accountability depends on how other treat it.

For example, a child can't be (legally) held accountable for signing a contract, but we still consider children as having identities. And corporations can be held accountable, even though we don't consider them as having a (personal) identity.

Maybe one day society will decide to grant AIs accountability.