US cities pay too much for buses

Don't be fooled, paying less won't help much since the cost of a bus is a small part of the costs of running a bus route. about half your costs are the bus driver. The most expensive bus is still only 1/3rd of your hourly cost of running the bus. If a more expensive bus is more reliable that could more than make up for a more expensive bus (I don't have any numbers to do math on though).

Half the costs of running a bus route are the driver's labor. The other half needs to pay for maintenance, the cost of the bus, and all the other overhead.

I'm hearing you say we should have self-driving buses... which is feasible since their route is fixed.

It is absolutely not feasible (yet), most of the job of the bus driver is knowing when to break the "rules", because someone is parked in the bus stop, or traffic is backed up so it make sense to stop a bit before the stop to let people off, or when to stop for longer than usual because someone needs to use the bike rack on the front, or when to use the bus kneeling feature because someone with mobility issues needs to get on or off, or when to skip a stop because your bus is too full and there's another right behind you, etc.

This is ignoring payment issues (hopefully it would be free anyway), answering riders' questions, being nice and letting someone off halfway between stops because it's 2am and pouring and they're the only one on the bus, and so on. I guess the general theme is that unlike Waymo where everything is ordered and planned out ahead of time and the car just needs to go from A to B, a self-driving bus will need to be constantly updating its plan in real time based on the conditions outside and what people on the bus need. It's not like a train where it can always stop in the exact same place and open the doors for a pre-defined amount of time.

It's obviously not impossible, but bus driving is much more complex than taxi driving despite the predictable route.