This is just what I said, that the figure of ~200 million years came from the age of the deposited strata. And I repeat that it seems specious to say that nature took this amount of time to form the rock that these yahoos toppled. Why not call it 10 billion years in the making, as we may say of anything we come upon at any time?
In sedimentary rock, the age of the deposition is what provides the time frame of the rock formation.