soberups
Pees in the brown Koolaid
The batteries on newer generation drones are all lithium ion, which overcomes a lot of the hurdle. The materials they also use are extremely light, like carbon fiber. We had drones at my university that were small and could actually fly around for a number of hours without needing a charge. The power to weight ratio isn't impossible to overcome with current gen batteries. The issues become more of battery life. These things can't make 25 stops with one charge, they're going to be limited to essentially amazon envelopes under 10 pounds in the current form and under 5 stops. Not efficient with our set up.
How well and how far would those drones have flown if you hung a one-gallon jug of milk underneath them? A gallon of milk weighs 10 lbs. All of the battery-powered drones I have ever seen were made of foam and carbon-fiber and they weighed a pound or two at the most. OK, multiply that by a factor of 10, put a heavy duty lithium ion battery in it, and you have a 10 lb. drone. Maybe that drone can fly for some distance like you say, but when you hang 10 pounds of cargo from it you have just doubled its weight. This would be the functional equivalent of putting 2500 lbs of lead in the trunk of an economy car, although with a drone it would even be worse because of the aerodynamic drag of the cargo plus any headwinds it might encounter. Its not going to work. Lithium-ion batteries aren't even going to get us close to the power-to-weight ratio we need to make drone deliveries a viable option.