Re: Can we have them
In fact there's a perfect use case near here. There are two villages on either side of the A36 to Bath, both with narrow streets. The bus service to Bath takes quite a while to navigate the villages.
A driverless microbus could travel around the villages and pick up and drop passengers at a bus stop on the main road. It would be a fixed route. It would save time, driver cost, and allow a more frequent service.
I am sure many other places have the same opportunities - I recall a bus service in Newcastle that goes round a sequence of housing estates parallel to a main road, another opportunity for a fixed route with dropoff points on the main road to the city.