If that's the case, then why haven't other PC manufacturers come in and swept that market from them? People still buy iMacs and MacBooks in droves and they glad

If that's the case, then why haven't other PC manufacturers come in and swept that market from them? People still buy iMacs and MacBooks in droves and they gladly pay those costs. If there was nothing more than an arbitrary Apple Tax (instead of something more real like R&D costs, build costs, etc.) then it should be easy for a company to ape what Apple has done, charge slightly less, and completely remove them from the market. They haven't and they won't for precisely the fact that it's not just an arbitrary markup.