Parties do _not_ have to trust each other to work in a permissioned or consortium block chain. They just don't. They do have to be non-anonymous to each other

Parties do _not_ have to trust each other to work in a permissioned or consortium block chain. They just don't. They do have to be non-anonymous to each other, and they might have to sign up to a legal agreement between each other (brokered by the governing entity convening the ledger, who issues certs to organizations so they can participate). But they don't have to be trusted. All you need is intrinsic interest in being on the ledger - some kind of pain (be it staked value, getting kicked out of a market, etc) if they are found to be a bad actor, which would be pretty obvious, and many bad actions can be prevented in the first place (e.g. prevention of double spend).