Well, Google doesn’t know anything until you go to a Google page either. Not counting things like Google Analytics, of course, but publishers choose to share that info with Google.

Google Chrome, when signed in, uploads your web history to Google by default.

Emphasis "when signed in".

You don't need to sign in. Everybody knows everything about you. Whether it's through tracking cookies, or through Google Analytics, or through device fingerprinting.

Google quoting privacy concerns is especially disingenuous, as they can track you and your activities across multiple devices.