I think it is possible to market privacy and security to casual users, but it's far more difficult to market anything to the privacy and security crowd. Apple has succeeded in their privacy marketing, I'd argue, because they already have a huge number of casual users.
Yeah I don't think being "privacy centric" has won over apple. It is their hardware/software integration and the mass market appeal they've built on top of their ad campaigns. I use apple stuff everyday and it is as stable as linux for me and much preferred to windows because of the constant invasion of privacy that is Windows 10.
