I've heard this argument a lot, but is the bus driver really more than a rounding error on the balance sheet of the transportation company? I have no experience in this field, but I would imagine the infrastructure for buying and maintaining a fleet of busses, creating a route network, dealing with ticketing, dealing with disruptions, etc, etc, makes up most of the costs around running a public transport company?
I think the benefit to transportation companies would not just be about salaries, but also about predictability in staffing. I've experienced a few times in the past that a strong flu season causes specific bus lines to be serviced with reduced frequency due to staffing shortages.
But concretely, regarding the staffing costs, if I roughly read the financial report section correctly, it looks like for the Berlin transport agency, salaries make up half of all expenses[0]!
Given that that's such a big portion, I think autonomous buses could likely unlock a lot of mobility in big cities by having more flexibility in creation of additional bus routes (as you don't have to consolidate multiple routes into one because you have to pay drivers for each).
