I'm by no means an expert on cars, but my impression is that they're one of the worst cases of a class of product that should be substitutable, but isn't, because there probably is only one or two makes & models that are close to fulfilling one's list of requirements, and if those are not available, it becomes a painful exercise of letting go.

Unless we consider begrudgingly buying an option because you need something to be buying a substitutable good. Which I guess is fair in some sense, but makes it feel like buying things is a loser's game.