Our track is IHRA. I have been watching street bikes go 9's without a roll cage for years. Not sure how a Demon or Tesla would be any less safe than a Hayabusa.
Crash a car at those speeds you get hurt. Add a cage. So they need to keep the injuries to a minimum. to lessen the medical payments
Crash a bike at High speed your getting seriously injured with a helmet on. the insurance keeps paying your medical
Get rid of the helmet and your dead. One time minimum payment.