I would love to data mine what Google has on me. I'm sure I'll get a copy someday. Almost everything on the internet eventually is released via acquisitions, subpoenas, hackers, etc...
Maybe they've just not got enough data on you?
"We will not combine DoubleClick cookie information with personally identifiable information unless we have your opt-in consent."
So you can't really expect them to be able to cough up the contents of profile 0x3f47d0387acb94857 when asked for the history of your account, if they are forbidden from joining the two domains together.
You should read this and reconsider. From the article: "The change is enabled by default for new Google accounts. Existing users were prompted to opt-in to the change this summer." https://www.propublica.org/article/google-has-quietly-droppe...