Amazon made the proposal at NASA's Ames Research Center in Moffett, Calif., urging that high-speed aerial UAS receive their own airspace located between 200' and 400' above ground level. Less capable UAS would be restricted to between 0' and 200'.
Airports and CTR's are no-fly zones for UAS. This will then be about the only places where manned aerial vehicles can land or fly low.
Where does this leave helicopters and off airport landings? While the law in some countries somehow restricts those to emergency or security services, I wonder how the swarm of drones will give way to an EMS helicopter touching down on Trafalgar Square. After all, if UAS could sense and avoid (like manned aircraft) there would be no need for "Amazon's private airspace".