I can't say anything about the hybrids, but both my wife's 2014 Escape Titanium and my 2015 F150 Lariat have electric power steering and it is NOT drive by wire. If you hit the start button without pressing the brake to turn on in "accessory only" mode, that unlocks the steering wheel; you can then turn the wheels with manual steering (although like a hydraulic system, much heavier than simple manual steering). The electric power steering on both of these vehicles is merely "power assist" much like hydraulic systems have been for decades. The physical connections between the steering wheel and the tires on the ground all still exist as they have for decades. Only the way your efforts at the steering wheel are assisted have been changed.
As far as I know, drive by wire on most vehicles is limited to the accelerator. Some newer cars are starting to include braking in the drive by wire systems. I haven't seen any mainstream production cars with drive by wire steering. "Drive by wire" indicates there is no direct physical link between components; only wire.
A bit of a lazy throw-away line on my part..... in my sometimes oblique way what I was getting at is that as control systems go, it's not that big a deal - technically. However, putting even just electric-assisted steering into a production vehicle at low cost, and having it run reliably for something like 15 years, is more difficult than it may seem.
Once you have even just one sensor is a sub-module, then you are faced with the question "What happens when the sensor becomes flakey ?". Quoting from the above link "
I have had many close calls when without warning the steering becomes almost locked up but have been able to so far muscle it around the turns. "
From an engineering standpoint, I take general issue with systems that trade-off reliability and baseline performance for alleged higher-value gains.
Obviously, nobody wants to deal with erratic steering, ever - that's a bad enough scenario on dry pavement - with what most of Canada gets to drive on 6 months of the year..... no thanks.
W/O high levels of vigilance and effort (even sometimes with them.....) As complexity is added, more critical failure points can arise..... There was a fatality in California after a brother drove his sister to their high school, and locked the car from the outside with the fob, so his sister could have a nap before her later class started. She passed away, trapped in an overheated car she couldn't escape from.
At the time, the way BMW had the car programmed, you couldn't open the doors from the inside, if security had been armed from the outside..... When I say that I'm big on baseline (aka, critical) functions always working, it's more than just my OCD talking....
I have worked with precision industrial servo-motors..... what I've seen coming out of cars with failed Eracks are not in that class, at least after a number of Winter's road-salt has had it's way...... back to that price-point thing, once again.....
Rgds, D.
To your point.... this has been going on a long time.....