This is one hurdle they need to overcome right now. No one is ready for a completely driverless vehicle on the road. Overtime it will one day be the alert is never needed or that the driver actually caused the wreck so they will then say remove the driver and let the computer handle it.
Also the computers are still working out the bugs...eventually it will be 100% robot and humans won’t be allowed to drive.
So, the trucks then will be controlled by SKYNET and HAL 9000 computers.