No one expected Dragon to survive those conditions, so they never bothered adding that code. It's just a cargo ship, so it doesn't really matter. After having

No one expected Dragon to survive those conditions, so they never bothered adding that code. It's just a cargo ship, so it doesn't really matter. After having learned in real world conditions that it can handle those sorts they figured, what the heck... might as well add it. The crewed Dragon (Dragon 2) uses powered thrusters to push itself away from a failing rocket.