Google claims here:
We strictly uphold responsible data practices designed to respect your privacy. That’s why we never use the content you create and store in apps like Drive, Gmail, and Photos for any ads purposes.
However, as recently as 2017 google was targeting ads based on users' gmail content, according to the New York Times:
Google plans to abandon its longstanding practice of scanning user email in its Gmail service to serve targeted advertising.
Is this not in violation of some U.S. law related to false/misleading advertising?
The phrase "we never use" seems to imply that this is something that they as a company would not ever do (which is untrue since they did it in the past), but it is unclear to me how this statement would be interpreted by regulatory agencies.