I think in The Netherlands the rule is that when they are a danger to themselves or others they can be forced to be treaded.
Imho this is a very clear line.
Imho this is a very clear line.
This is not even to mention that disagreeing with the Party can become very dangerous to yourself... (Not so much in the Netherlands, but elsewhere, possibly. The soviets used forced institutionalization against their political enemies.)
Which brings up the next problem that what will be enforced is perceived risk, not actual risk. Per billion-vehicle-miles-traveled, private pilots are as safe as car drivers around 11 or so deaths, but much more common activities such as bicycle commuting is vastly more dangerous around 31, and simple walking commute is even higher around 36. Speaking of bicycle commuting, that brings up the third dimension which is political, in that aggressive public support of bicycle commuting is a hipster sacrament not to be interfered with. Speaking of politics, AOPA is not really a group to be messed with, so even if private pilot flying were more dangerous, it might not be a fight worth picking for bureaucrats. And finally the forth dimension is time; its possible, in fact nearly certain, that private pilot flying was at one time, perhaps 1925 or 1955, more dangerous than driving in 2018, however influential or profitable that might be in 2018 it would be bad justification for legal enforcement in 2018, in a sort of affirmative action sense that my grandfather was a "very dangerous private pilot" in the WWII era therefore I should be punished for his actions by making it illegal for me to fly...
It's a question of whether we rate the travelage by utility or by luxury. If we consider it for utility, vehicle-miles travelled is a perfect metric. If for enjoyment, time spent traveling is better (but still not perfect).