It's very very easy to be cheaper than a helicopter. Drones can require zero or minimal labor, move fast, and run on electricity.
If we can have them carry a decent weight and have good reliable ways to get them from and to where they need to go, they will revolutionize delivery. Door dash will be obsolete.
In addition, the Amazon/DoorDash model isn’t even what we’re talking about here - this is a predefined, specific route with the last mile still handled by conventional vehicles, so it is even worse.
If we could all have landing pads like we have mail boxes, something with a fence, it would be much better.
You don't leave it free space because then you have all sorts of drones whizzing around in all sorts of random and uncontrolled directions and that creates a lot of clutter that will cause crashing.
Is there really?
I understand that for non-fungible, perishable goods such as organs or test samples there might be a need (though a helicopter would do just as well), but when it comes to supplies, it will be significantly cheaper to just make more of them and stock up on them at each hospital rather than moving them back & forth (not to mention that this particular trial only ranged for 40 miles - this is something a car can easily do).
It won't work unless it's cheaper than the alternatives, and I can't see it being cheaper than just optimizing logistics elsewhere to ensure you have a big enough stock of medical supplies to not need regular drone deliveries (and when you do, a helicopter is an adequate backup plan).