I don't know that I fully agree with this. I think in even well functioning teams you need at least one person who is empowered to make the call. In the cases of a disagreement deadlock you need someone to break the deadlock. Whether that person is a called a Tech Lead or something else you still need them and they need authority and freedom to make the call.
Maybe his Mediator can be that person but if you give the Mediator the power to break these deadlocks then you need to ensure that he has enough practical experience to make sane choices. And if you have a Mediator with the authority to break a deadlock and the experience to do so with mostly correct decisions you have what most people call a Tech Lead.
Maybe his Mediator can be that person but if you give the Mediator the power to break these deadlocks then you need to ensure that he has enough practical experience to make sane choices. And if you have a Mediator with the authority to break a deadlock and the experience to do so with mostly correct decisions you have what most people call a Tech Lead.