Have owned pickups for a number of decades. Have never thrown anything over the side nor grabbed anything to pull out from the side. There’s a number of reasons why a person wouldn’t do that; they’re short, other physical impediments like bad shoulders/being older, the item they want to put in or take out is heavy or ungainly, they don’t want to risk unnecessarily scratching the paint, etc…
Do you know what’s established? Billions of ICE vehicles. If Tesla had designed an ICE vehicle, slam dunk and quicker to market.