Regulation is unfortunate, but necessary. At a little over 1.5 lbs., the Mavic pro could be fatal if falling from even 100’. Slim chance it would land one someone, but if it did? Also, wildlife (which has many laws & regulations to preserve and protect) could be at risk as well.
And, it might not seem like it, but a little drone could do a lot of damage to manned aircraft, big and small.
A single prop plane’s body or windshield could be smashed by a stationary drone at the planes’ own airspeed (120+). A jet engine could be disabled by a drone being sucked in and wreaking havoc within the various chambers.
US also has the most congested airspace in the world, so for everyone with $500 to spend on drones capable of height & distance, that adds a lot more chances for something to go wrong.