Within a short time the things would cover the ground, and the roofs of all buildings.
Things to think about that the designers don’t want us to think about:
- they will find their way into storm drains and from there into the ocean.
- some will fall in waterways and from there go to the ocean.
- they will be ingested by ocean life, with foreseeable consequences.
- they will get into your nose and lungs, with unknown consequences
- birds will eat them.
- they will get into jet engines with unknown consequences
- they will soon be in your house, tracked in on your shoe mud and on your dog
- your dog and cat will eat them, with unknown consequences
- they will be on your hair when you spend a few moments outside
There is no way to collect them once they have been released, or to track them. This is truly irreversible.
The designers should not be given the power to proceed.
I think there was a similar plot point in a SF book I read. An arms race for nanobots and nanobot filters.
https://en.wikipedia.org/wiki/The_Diamond_Age
IOW, just because you can doesn’t mean you should.