The "problem" depends on who you ask.
For the big companies that want to begin running drone deliveries, they don't want pirates scanning for drones and hitting their deliveries afterward. They want an Internet beacon.
For drone racers, they just want to fly without the mandatory hardware (and weight), and all the mandatory pre-flight checks of a Cessna for an FPS drone the size of a chicken and 1/8th the weight. There's also the Big Brother aspects that not only are pilots required to run one of these radio tattle-tales at all times, but Freestyle pilots especially like flying in areas that the FAA won't allow (i.e. around buildings and other structures).
For hobbyists (this group encompasses most of Slashdot and most enthusiasts), they don't want to have to pay (Money, weight, and power) for hardware that does not benefit them. As a rule, they just want to fly their devices with as little interference as possible.
To date I haven't seen anything about the DB of IDs being public.