Anytime you build in safety margins people are going to push it. The extra runoff tarmac at so many tracks prove it. People look for the limit and if they cross it they just cruise back onto the track and no harm no foul. This encourages more corner speed because the stakes are so much lower. Get rid of TC and the same guys will still be upfront, but laptimes will slow, because you can only bounce on your head so many times.
As per bike versus car safety. I once was the first one to crash in Friday practice and broke a bunch of bones. They carted me to the hospital and the nurse commented that "we" were racing so they could expect some extras patients that weekend. However she said we kept them busier but the car guys were usually bad when they came in. Head and internal injuries versus broken extremities.
"Remember that an enduro tests the endurance of three things: your machine, your body, and your wits. Only one has to fail to keep you from reaching the finish line." Cycle World March 1966