A license does not make one a good driver. Paying attention to what you are doing and a little common sense does.
We would have died before we hit someone or something because our privilege would have stopped right there. Same with operating a boat.
Where I see registration going with drones is that if there is a problem, and you are a registered owner in the area, expect a visit from the authorities. It doesn't mean you were the problem, just that you will be scrutinized, at the least.
Of course, (illegal) unlicensed drones might be the source the problem (and of your pain), but that never stopped the authorities from leaning on the people who did things right.
I think the parallel with firearm ownership becomes apparent at that point.
My son drove a large farm truck full of melons across state boarder on interstate at age 14. All legally because he was a farm employee No license required