I think that's where BEV and L4 autonomy comes in once it's commodified. Buses are huge in part because of having to amortize the driver and that makes them very crude. An autonomous mini-bus that can fit 10 people would fit more organically into cityscapes, destroy the pavement less, be run at 20% of current headways, etc, etc. Honestly the only big issues there I can think of are seatbelts (lower mass means that it may decelerate much more rapidly than a normal bus in an accident) and accessibility.