Comment by bregma

It's not all about the realtime. It's also about the process isolation. If a Linux driver crashes, it takes down the entire system. If a QNX driver crashes, it's not part of the kernel so it can just be restarted. It's not good to wait for 5 or 6 seconds for your car to reboot so your brakes will start operating again while you careen towards that retaining wall on the highway.