Robert Woolley wrote:

c) The world has moved on from crew operated buses....

Others have answered your other points, but this is just untrue.

Europe and North America may have few crew-operated buses, but in the
rest of the world, where most bus passengers live, crew operation is
the norm.

And it wouldn't take an enormous change in the relative costs of fuel
and labour for RMs to be more economical per passenger mile than heavy
modern buses.

Colin McKenzie