Having been a driver for Amazon in the past for around a year and a half, I’ll tell you right now that these bikes wouldn’t work in a lot of places Amazon delivers. In dense urban areas? Sure, but certainly not out in the ‘burbs or rural areas.
Package counts on those routes can top out around 500. There’s no way Amazon would purposely reduce the amount of work they lay onto one driver.
Now that being said, if they loosened their iron grip over the drivers then I can absolutely see this happening in downtowns and some apartment complexes. Outside of really densely packed areas, it doesn’t make a lot of sense.
Some routes have drivers going well over 100 miles in a day. No way anyone’s gonna do that on a bike. And in the middle of summer in southern cities? Forget about it. Amazon doesn’t even give drivers enough time to find a bathroom, no way they’ll allow drivers to take breaks to cool off.
It's the kind of thing that's going to work in some areas and not others. It'll be much more viable in most of Europe for instance as overall it's much more urbanised than the USA.