That's not correct. You can have a third party that is trustless, ie that cannot perform any action on its own that would favour or harm you.
Take for instance the role of Plasma operator or Lightning Channel operator; The role allows for a third party to have the costs of setting up infrastructure for you to use, but at no point are your funds held by the operator and you are always able to exit a contract if you submit on-chain evidence of fraud.
That's not the case in many (most?) of the cases I mentioned.
In plasma for instance, the operator and seller could collude against the buyer but any "illegal" operation they do on-chain is enough for anyone to trigger a mass-exit and cause financial and reputational loss to the operator.
A common theme in all the on-chain payment technologies I mentioned is that they do not put any one party in "charge" but the volunteers who run staking channels of any sort (plasma, lightning, etc) can and will suffer financial damages (loss of deposit, etc) if proven to act maliciously.
Are these guys really add more value to the economy than chargebacks? I very much doubt it.