In city centres with high rise blocks, I would expect that a van would be much more cost effective, allowing a lot of stuff to be delivered to effectively a single point in one go.
In massively rural areas the delivery in a few minutes from order is a difficult concept. If the nearest town is 30 miles away the drone needs a range of 60 miles at high speed for each delivery.
Small to medium towns plus suburbs of cities probably give the best population density coupled with individual properties having enough outside space for the delivery to be made. In weatherproof packaging, obviously. However to meet the "few minutes" delivery target the stock would have to be held locally which defeats the current centralised warehousing model.
Expect the "few minutes" to morph into a few minutes after the monster delivery platform arrives within 5 miles of your location and starts firing off drones left right and centre. Amazon Prime "next day" delivery is already moving in this direction.
Anyone who has watched good tracking information (DPD for example) will have seen the delivery truck arrive very locally hours before you get the package. The courier in two streets away and on delivery 23. You are delivery 76.
Presumably this is still much cheaper than the van turning up in a local car park and a swarm of Deliveroo type cyclists rushing all the packages out at once. Which is more or less the drone model but with zero hour contract meatsacks.