Stalkers gonna stalk, makers gonna make, founders gonna found. We nerds always knew that the Facebook, Google, etc. images were tracking beacons, and their business model was, to paraphrase Eric Schmidt, to get as close as possible to the creepy line. Fortunately, it is/was easy to opt out by DNS-blocking a few hosts. If this behavior becomes common, back-end data sharing and syncing will become the norm, and something like ToR will become necessary, then local encryption, then...

But who ever said fighting crime was easy?

EDIT: "And I have no doubt that the vast majority of engineers, designers, and policy makers working in Silicon Valley want to do the right thing."

How can I even pretend to believe that the author believes that? They mostly don't know what the "right thing" is, don't think of their behavior in moral terms, and wouldn't dent their salaries to act morally.