Yet, in aviation, we have the "experimental, amateur built" (or, E/AB) category of homebuilt aircraft which is going strong and honestly I'd say that most of the technical innovation happening in light aircraft is happening in the E/AB category. There are thousands of homebuilt kit aircraft safely flying in the sky above you right now.
The difference, of course, is that for obvious reasons, aviation has developed a pervasive culture of safety and rigorous root-cause analysis whenever an accident happens, and deadly crashes frequently result in regulatory corrective action. If car accidents were as rare as aircraft accidents, the NTSB brought a team of investigators whenever one happened, and the results of that investigation led to stricter laws and enforcement, we'd probably be OK with kit cars, too.
The sad truth about automotive is that crashes are so routine that police won't even get out of bed unless there are injuries. And, there is basically no penalty for negligence that leads to a car "accident". It's almost impossible in the USA to lose your driver's license, even after dozens of repeated DUIs. Totally different cultures.
The difference, of course, is that for obvious reasons, aviation has developed a pervasive culture of safety and rigorous root-cause analysis whenever an accident happens, and deadly crashes frequently result in regulatory corrective action. If car accidents were as rare as aircraft accidents, the NTSB brought a team of investigators whenever one happened, and the results of that investigation led to stricter laws and enforcement, we'd probably be OK with kit cars, too.
The sad truth about automotive is that crashes are so routine that police won't even get out of bed unless there are injuries. And, there is basically no penalty for negligence that leads to a car "accident". It's almost impossible in the USA to lose your driver's license, even after dozens of repeated DUIs. Totally different cultures.