Driverless trucks as distribution centers/battery swaps, and rooftop drone stations, could bring this down to last meter delivery, rather than last mile delivery. You just need delivery from curb to door step which a truck can now do and multiple drones can be delivering packages at one time.
Going to back-of-the-napkin this here: Current cost (just for person making the drop) is about $1.50/stop. Assume six packages/stop. So now you just need six drones to fly a single package from a truck to the doorstep for $0.25/each in that stop. So each drone will need to make 120 such runs/day for under $30.00 ($150/week, $7,800/year). This should be enough to easily cover energy/CAPEX as I assume that drones would be operating autonomously, and maybe you'd need one override-pilot in a support center for every 100 drones (basically one manual override every 17 stops).
Given the sanity check above, I'd wager that you could easily get this down to $0.05-$0.10 per package, including edge cases covering 99% of the deliveries. Big deliveries like TVs may ask the owner to come out to the (driverless) truck to pick it up at the side of the road while a drone century waits.
Going to back-of-the-napkin this here: Current cost (just for person making the drop) is about $1.50/stop. Assume six packages/stop. So now you just need six drones to fly a single package from a truck to the doorstep for $0.25/each in that stop. So each drone will need to make 120 such runs/day for under $30.00 ($150/week, $7,800/year). This should be enough to easily cover energy/CAPEX as I assume that drones would be operating autonomously, and maybe you'd need one override-pilot in a support center for every 100 drones (basically one manual override every 17 stops).
Given the sanity check above, I'd wager that you could easily get this down to $0.05-$0.10 per package, including edge cases covering 99% of the deliveries. Big deliveries like TVs may ask the owner to come out to the (driverless) truck to pick it up at the side of the road while a drone century waits.