But then how do you deliver to the upper floors of vertical buildings? That must be half the near-term market for these kinds of drones: people in dense, urban areas well-served by local droneports, who are looking for convenience above all else.
If you can't safely manage urban canyons—you can't manage. It'd be like selling self-driving cars that are only approved for private racetracks.
Here's a curious article I read the other day, that underscores the market factor:
https://news.ycombinator.com/item?id=45445406 ("What It Takes to Get Lunch Delivered to the 70th Floor in a Shenzhen Skyscraper (nytimes.com)" / "An informal network of last-mile runners close the gap between harried delivery drivers and hungry office workers in a Shenzhen skyscraper")