Most people I know use gmail, and not a single one of them is thinking of changing due to privacy concerns (as far as I know). What better option is there for a non-technical person anyway?

80%+ of people who own smartphones use android, and they have phones for most niches - big, small, cheap, stylus, unlockable, replaceable battery etc. They have several manufacturers making phones with it. Their position there is not fragile either.

I'd love to see Firefox take off, but there is no way it is going to be bigger than Android.

Sure, there is a very small chance that everyone will stop using Google's products, but the chances of people moving off Facebook is much greater.