Why do you think they don't do root cause investigations?
I've personally read through the root cause reports for most of the notable AV accidents. They're not always quite as intensive as aerospace, but I'd be hard pressed to describe any of them as wacky statistical arguments.
Obviously most of those reports aren't public, but I'm assuming you also have industry access.
Key point: the root cause investigation is not driven by the company involved. The FAA and the NTSB investigate and can by law demand documentation from the company.
I've personally read through the root cause reports for most of the notable AV accidents. They're not always quite as intensive as aerospace, but I'd be hard pressed to describe any of them as wacky statistical arguments.
Obviously most of those reports aren't public, but I'm assuming you also have industry access.