One would have to be quite a weakling to lose control just because power assist is gone.
When the car is in motion, very little strength is needed to control the car. At rest, the situation is somewhat different.
I think there’s a lot more than power steering that that could be interfered with. I suspect, although I don’t know for sure, that if you could hack into a car’s computer system you could probably cut out the brakes, except for the mechanical hand-brake, and I’m not sure if even that is entirely mechanical these days.
And you could probably mess with the steering. And I suspect put it on full acceleration.
None of those are normal processes, but if you have a computer involved in mechanical processes, between the cup and the lip as it were, then almost anything might be done by a really knowledgeable hacker. And, if necessary, they could send someone to crawl under the car the night before and make a few extra connections. Stuff that wouldn’t be too noticeable after the car had been wrecked.
While I agree with you Cicero, don't tell my wife she is a weakling (she is!). When my drive belt broke she was just turning into an intersection, and had the impression the steering had locked. The car was moving slowly, and had there been oncoming traffic, she claims she would have hit it head on. I believe, but she didn't report, she lost the power brake assist as well. But the engine was still running, and she was only a block from home, or the car would have overheated, since the water pump is also driven by the universal drive belt. She discovered she could wrestle the steering sufficiently to negotiate the turn around the block, but steering systems with front wheel drive is not what it used to be - not like driving a VW or my old MG.
You probably know that there has been research for decades into automobile guidance, either usually based upon sensor strips embedded in the road or beside the road. Those technologies do require full vehicle control, but are not ready for prime time. We have had enough trouble controlling trains where steering is not an issue. The queuing theory problems turned out to be daunting. The multi-billion dollar Bay Area Rapid Transit was designed for automated thirty second intervals between trains over forty years ago, but the computer control technology wasn't nearly ready; neither were the computers, synchronization between them, nor the theoretical problems solved. Bart trains still have overpaid operators (at over 150k/year) who use radios to communicate how fast they can go and if there are obstacles ahead.
My impression from my wife's report of CNN broadcast on the Hastings crash is that there was a pursuit going on and Hasting’s car was pushed off the road as we've seen happen in action movies as stunt drivers and some police are trained to do.