Birds, PPLs, model aircraft, etc., are all completely irrelevant.
Whatever baseline risk they collectively represent today, drones add new safety concerns above and beyond that baseline.
We're only at the inception of the drone age. There are already over 500,000 drones sold in the US alone and the drone market is expected to grow exponentially in the next decade when shipments of drones are expected to be in the millions (!) of units each and every year.
Casualties due to unregulated drone use is a matter of when, not if.