There are several “last meters” delivery robots developed.

Short range drones are being used in Australia.

And I heard of at least one company working with apartment architects to standardize a “port” on the building exterior to which a truck/robot would connect to “inject” packages to the inside.

> "Short range [delivery] drones are being used in Australia."

Last I read (late 2023 IIRC) these were being cancelled in various areas, if not everywhere? People in neighborhoods were getting annoyed by the noise of drones buzzing overhead.

Like some sort of "mail chute"?

This was just an acquaintance some years ago in SF, but I recall it was fancier with conveyor belts and a protocol for the robot to communicate the size and weights of the packages being delivered.

Tiny catapults. It's the only correct answer.

Sadly, this would still be an improvement on many smaller delivery services that especially Amazon is fond of using.

The slaves obviously.

But to be serious, there may be a way of doing it, it just seems very far off unless you're talking about Amazon hub or something like that, where it would be more feasible (but still difficult to achieve).