The Internet generally and the business models of consumer tech companies specifically mean that the default outcome is the end of privacy.
The Facebook brand is, due to Facebook’s strategic choices, about not respecting privacy. That is why the Cambridge Analytica story is such a problem for the company.
Facebook has long had too much power, but Mark Zuckerberg’s expressed willingness to use said power for political ends means it’s time to consider countermeasures.
The nature of the Internet and the business-models of social networks means that privacy as commonly understood is dead; tech companies need to learn to self-regulate or governments will do it for them.