The least they could do
A 55 lb drone travelling at 100 mph could do fatal damage to an aircraft, so it's vital that they are restricted to different airspace. Because they don't appear to move relative to each other, it's hard enough spotting a light aircraft on a collision course, never mind a small drone, so these regulations are the least the FAA could do. I think that eventually they will be obliged to carry transponders which broadcast their location, so that they can avoid each other, as well as alerting other aircraft. Two 55 lb drones which collided with each other could make a nasty dent in anything they hit on the ground.