We can also make the bus smaller. And to give the passengers more agency, we can let them drive it. Instead of paying bus fare every time they board, they can pay a larger up-front cost for this bus, and of course, ongoing gas & maintenance. To make sure they don't pose a danger to others, they can also purchase insurance, and of course have some sort of license to operate it.

Where I live, the bus line that serves me only has maybe one marked stop. There's a bus depot at the ferry; every where else, you can just stand on the side of the road and wave your hand when the bus comes by and it'll stop for you; when you want to get off on your way home from the ferry, you push the button and let the driver know where to stop.

But that only works because density is low and there's only one plausible destination.

Most optimization is a curve. Arguing for moving closer to the top of the curve is not the same as arguing for moving all the way to the minima on the other side. But why do I have to say that?

Some bus systems actually essentially do this for a fraction of buses.