We examine three common principles underlying a slew of “privacy-enhancing” techniques recently deployed or scheduled for deployment by big tech companies: (1) “We deny (or throttle) access to your data by third parties!”; (2) “We minimize the use and retention of raw data!”; and (3) “Your data never leaves your device!” Our article challenges these principles, not on the grounds that techniques offered to implement them are unsuccessful in achieving their stated goals. Instead, we argue that the principles themselves fall short because their underlying conception of privacy is flawed. Through philosophical analysis and technical scrutiny we reveal the misalignment between principles and a sound conception of privacy. We reinforce our findings, empirically, with a series of factorial vignette user studies, which demonstrate a surprising gap between principles and actual privacy expectations.