Those extra journeys can be minimized with decent routing software. Even if it's as simple as ending up at B, then going directly to the nearest customer waiting for a ride.

And fwiw, if Tesla gets their robotaxi stuff working, their 22-passenger "robovan" is basically a bus anyway, just without a driver.

I doubt that's a big factor.

The big thing they do is to make a huge number of parking spots obsolete!

There will also be far fewer cars doing the same transportation work.

Bro just platoon the autonomous taxis into a convoy, give them separated lanes, and get rid of the rubber wheels and add steel wheels and steel lane guides for maximum efficiency. It's obviously new and revolutionary!