Re being a commercial feeder, that's like lots of things, if individuals start refusing to bear the cost of obtaining hours, airlines will be required to make changes. They might increase pay for pilots, lobby for changes to the licensing process or provide alternative ways to get those flying hours (I'm not sure how you subsidize hours without perverse incentives, but I guess you could protect investment using loans that had forgiveness for service).
You've pointed out some purposes that GA fulfills, but you haven't addressed what harm those lead emissions are actually doing. It could be minimal. Or, it could be pretty severe when you look at the aggregate impact. At a structural, societal level, poisoning people to avoid higher direct costs for air transport is likely not a good trade-off, so it is necessary to look at both sides of it.
Re being a commercial feeder, that's like lots of things, if individuals start refusing to bear the cost of obtaining hours, airlines will be required to make changes. They might increase pay for pilots, lobby for changes to the licensing process or provide alternative ways to get those flying hours (I'm not sure how you subsidize hours without perverse incentives, but I guess you could protect investment using loans that had forgiveness for service).
You've pointed out some purposes that GA fulfills, but you haven't addressed what harm those lead emissions are actually doing. It could be minimal. Or, it could be pretty severe when you look at the aggregate impact. At a structural, societal level, poisoning people to avoid higher direct costs for air transport is likely not a good trade-off, so it is necessary to look at both sides of it.