About 20x more expensive at 1/3 the speed vs commercial jet; 40x more expensive at 2x the speed of a car.[1][2][3] Car has 10x the range between refuelings and can stop at almost any building. This will presumably be limited to heliports, of which there are presently ~ 6,000 in the U.S.[4]

It's really a quieter / more comfortable helicopter. Helicopters have seen limited use. Will lower noise change that?

Edit: The dominant cost factor across modalities seems to be seats per pilot. It's infinite for cars modulo parking; in the hundreds for commercial jets; dozens for busses; single digits for taxis and small aircraft. Of course it's always been understood that ridesharing needs autonomy to be truly profitable, and from the slides it seems Joby acknowledge this as well. Autonomy may be easier in the sky...

[1] https://www.youtube.com/watch?v=a717YZnhQ-s&t=700s

[2] https://en.wikipedia.org/wiki/Available_seat_miles

[3] https://news.ycombinator.com/item?id=19574388

[4] https://en.wikipedia.org/wiki/List_of_countries_by_number_of...