My gut feeling is that the people doing UI design at Tesla don't have any experience in human factors engineering for vehicles or mechanical systems, and come from more generic UI backgrounds. For a website, playing "F around and see what works" isn't dangerous.
For a car, it's incredibly important to get it right. ESPECIALLY cars with a dearth of physical controls as fallbacks.
Unfortunately ,it's been exactly this for the last several major version FW updates.. it's clear they have absolutely no clue how to design and develop UIs for actual DRIVING. Each update pulls more and more attention AWAY from the road to focus on the completely braindead UI. IT SHOULD BE 100% THE OTHER WAY AROUND. Idiots, all of them, including Elon Musk who supports this path.