As a tech employee who has worked on software privacy controls for consumer devices at amazon I have a couple thoughts. First, let me clarify that I am still highly skeptical about any tech companies privacy promises. That being said, the privacy control I worked on for one of Amazon's devices was a pita. It was a hardware switch which completely powered down all sensors, and modifying code related to it required extensive testing to preserve customer privacy. Amazon at least emphasizes to employees earning and retaining customer trust. The real reason I actually semi trust tech companies privacy policies is the ethics of individual employees. Maybe I'm projecting my disgust at privacy infringements onto my coworkers, but I generally believe these large corps can't hire sufficient teams of devs to build privacy compromising systems without at least one person whistleblowing.

My $.02