1. Operating a heavy, dangerous piece of machinery in the field without learning how to operate it first is most certainly the operator’s fault. That’s careless, irresponsible, and endangers others. If they had hurt or killed someone, they would’ve been prosecuted and would possibly be in jail right now.
2. Taking a few moments to learn to click a button in a car you bought is far from unreasonable, especially when everyone knows going in that a Tesla is not a completely standardized vehicle. The risk posed by this change is orders of magnitude less than the risk imposed by swapping the brake and accelerator pedals, so that is far from a fair or reasonable comparison.
3. You may not appreciate the benefits of the changes that Tesla made, as these things are ultimately subjective, but those changes contributed to the Model Y becoming the best selling vehicle on the planet.
Now, if your coworker had rented a car and unexpectedly received a Tesla, I could sympathize more. A car rental company should not rent out non-standard vehicles unexpectedly. However, it’s always the responsibility of the driver to learn to operate the vehicle first before getting on the road and endangering others.