I already responded to both those comments, so you already know I don't think those comments are any refutation at all.

Cup-holders are not a complex engineering problem (as the first comment said), and the preferences of the European and Asian markets are irrelevant for cars that are, please recall, built specifically to be sold in the United States. Nobody sells identical cars in Europe and in the United States. They often don't even sell the same models in the US.

The response (of the second comment) boils down to "you are silly if you think you know enough to criticize the work of people who make cup-holders for a living". If you accept that as a valid response, that could be used to shut down all critical activity. It's the same as responding to #BlackLives Matter by saying "You can't criticize the police for shooting people unless you're a policeman."