It's not only unnecessary, it's dangerous. Even wifey's humble grandland had wondering why it was 'bonging' at me when I went to fill it up the other day. When I explained where I was and what I was doing she informed me I was probably too close to the car in front for the speed I was doing. What??
I told her I turned the heating on but could only see buttons for front and rear screen defrost, nothing to point the heat into the cabin. She said there wasn't a button for that, I had to go into the touch screen menu. What??
She asked if I remembered to turn off lane assist and stop start before I set off. I told her to fill the fickin thing up herself.
The Daily Mail's motoring correspondent wrote an article a while back saying he had just driven a new model (I forget) and it had buttons! He loved it.
Lane assist certainly is dangerous. It drags the car all over the road.
If I forget to switch it off I am soon reminded as it tries to drag the steering wheel from my hands.
Two of my cars have lane assist (which I very rarely use anyway) - fortunately, I have to activate it myself on both for it to work which isn't a problem. However the system on newer cars seem to set by default to 'activated' mode whenever the ignition has been off, which would do my tree in.
It's like being a pilot, I guess. Going through the cockpit drill before setting off - lane assist off, engine stop / start off, auto hold on.....