monsterer and smooth, I repeat again, how do you prove if a 51% attack is censoring transactions? In other words, how do you even detect it in an objective and provable manner?
A system which doesn't objectively (from the perspective of all observers) know when it is failing is not Byzantine fault tolerant.
Refer again to the Wikipedia definitions:
The following practical, concise definitions are helpful in understanding Byzantine fault tolerance:[3][4]
Byzantine fault
Any fault presenting different symptoms to different observers
Byzantine failure
The loss of a system service due to a Byzantine fault in systems that require consensus
This circular logic of yours is getting redundant. I have made my point and you have not refuted it.
Bitcoin employs an amortized byzantine consensus. Nodes vote with their hash-power on the branch of the chain which they consider to be truth. Evidence of byzantine failures is the existence of multiple branches; we call these orphans. Each branch presents a different version of truth to observers of the system.