The problem is they don’t have to even change the regs for it to be an issue. This is the fundamental problem with the “agencies” of the federal government, they are truly judge, jury, and executioner on all their own regulations. They don’t want to keep writing field approvals for some random thing? They just won’t, even if there is no supporting legislation or regulation. They don’t reeeeally want to certify that new aircraft or engine design? Well… they just won’t. They don’t really feel like approving that new unleaded gas or expediting its review or even working together to get something done quickly even though the alternative is just to let the eco-lobby litigate GA out of existence? Well, no bother. It goes on and on and on and on and on, and yes, I am steamed about it because I have experienced their malfeasance personally. You said 70s, but all of Part 23, as an example - the entire corpus of design standards - was implemented in the late 60s, I believe, so there’s a giant rewrite of regulation if I must point to something but there’s plenty more, and in reality, it doesn’t matter because it doesn’t even have to be about actual regulations. With Chevron overturned, there is new hope for at least the judge, jury, and executioner problem, but plenty of issues still remain and it’s not like the average civilian GA pilot has the pocketbook to take on the government anyway.