Earlier quoted context omitted.
Yesterday I was driving back from Scotland to England, doing 70ish, when we ran into a really heavy thunderstorm. Went from good visibility to almost zero in seconds, and the only thing I could properly see was the crash barrier alongside the lane. I found myself desperately trying to see where the road was, simultaneously trying not to get rear-ended as I slowed up, switch on the rear fog lamps and hazards, max wipe…
You know, when you take your drivers test in the US, you have to demonstrate your ability to know where all those functions are before you even pull away to start your test.
The question is not whether you can operate the controls under normal circumstances. It's whether you can do it when task-saturated with more important tasks. Under such circumstances, I simply wouldn't have had any attention left for glancing at a touchscreen, but I did know and could hit all the manual controls rapidly without looking.