>It costs Tesla $0 per vehicle to add a new button to their cars. It costs millions for everyone else. This is not a useless capability; it makes a difference every single day.
Complaint #1 about Teslas' from owners that I have spoken to is that the UI/UX requires total re-learning as opposed to other cars, and then when the re-learning phase is complete, it's still difficult to operate without full attention.
Sure, the argument 'Oh, they shouldn't be dividing their attention from driving.' is all well and good; but try convincing normal commuters that they should pull over to adjust the volume on their stereo. I don't think you'll win that one.
Tactile/physical components are just easier to operate without know-how, and without focus being pulled to them in its' entirety. The linear movement of a volume jogging dial is intuitive; there are two diretions on both the knob and the mechanism which is being affected -- it's direct, and obvious.
Touchscreens, usually, are none of these. Using a touch screen telephone is not an eyes off exercises, but dialing and talking to someone on any of my old flip phones or Nokias was. There was a fundamental shift from worrying about being able to do one thing very well to doing all things OK in the cell phone world, and I think that it's a shame that companies like Tesla think that this is a philosophy that should be pursued among auto-makers.
Thankfully, many automakers that were dead set on touch interfaces have begun to realize that they're not good everywhere.
Mercedes/BMW/Audi went away from buttons just to find themselves crawling back... and i'm okay with that. It makes the cars easier to operate, and less focus dividing on the road.