The data still goes to google. While the expectation would be that the data is only used by homebrew, there's no actual way of knowing that google isn't gratefully helping itself. And given the entire way Google's business works, they probably are.
I can totally see someone caving for the one and not the other.
https://www.google.com/amp/arstechnica.com/information-techn...
Does not exist like you think when it comes to projects. People are very secretive about lots of projects for all kinds of internal political reasons. Using data they technically have the right to use in a somewhat scummy way is a perfect example of a project that would be kept out of the spotlight.