There’s not a lot the support cars could do. Brammeier was out the back of the front group on the climb and chasing to get back on for the descent. Race cars would be following the front group – especially if the riders are one minute down. It’s the responsibility of the rider to pick their way through the support cars as they descend. Yes the support cars have to keep vigilant so they can keep out of a riders way – but that car had no chance the speed Brammeier was going.
The other two would have stacked it off the edge of the road had they not hit the moto. They’d never have slowed down.