I have been on a container ship, where the steering failed leaving port. We were only 16,000 tons, but it took almost half a mile to bring the ship to a stop with the engines full astern, if my memory serves. We missed Hythe Pier oil jetty in Southampton by less than 10 yards. We also had a pilot on board and he was white as a sheet when he disembarked. Nothing he could do about it.
This ship displaces 100,000 tons and at 8 knots, you’re looking at miles to stop it. With a total power loss, you’ve lost the ability to reverse the propellers. That ship was not stopping anytime soon.
That they were able to get off a mayday and the authorities managed to stop traffic on the bridge saved countless lives. This could have been a lot worse.