I find that people on HN frequently use the term "marketing" in the absolute broadest sense of "all activities involved in the process of creating a product that customers want to buy," but still use it pejoratively as in its narrowest sense of "advertising and other communication intended to convince customers to buy a product."
Yes, every feature is a marketing consideration. Marketing involves everything about how your potential and existing customers view your products, and privacy is a huge subject of interest.
That being said, there's nothing wrong with privacy being both a marketing move and aligned with our interests as users. In fact, I'm more comforted by the idea that morals and profits are aligned here, because no company is above choosing the latter when push comes to shove.
For example, how is Apple's emphasis on privacy, with the additional features they have added to push for it, different from their emphasis on backing up when they introduced Time Machine? I think that the Time Machine introduction was as much of a marketing move, at which point you've broadened the definition of the phrase where it doesn't really mean anything.