> My user account, system locale, browser locale, and keyboard settings are all set to English. I am logged into Chrome and all Google services. I travel to Germany every few months, and lots of services that I've been using for years suddenly decide I speak German.

This does not require more tracking. This requires LESS tracking - just show the language explicitly requested by the user.

> Netflix on Apple TV asks me to select a user every time I launch it. I've had this account for 15+ years, and never had more than one user on it. I always select the only option there is to select. There is no setting to disable this screen.

This does not require more tracking. Just dont show the screen if there is only one user.