Earlier quoted context omitted.
Simple. Google is in the business of collecting and monetizing my data and removing my privacy. I want them to have as little access to my life as possible.
They are in a business of showing you ads. Showing your private data to someone is not in their interest.
It's also been well studied how so-called anonymized datasets can be de-anonymized in various ways and then all the historical data is de-anonymized.
What you once thought was benign and not noteworthy can easily be used against you as the times and attitudes of a society change. Many examples can be seen both in modern day "cancellations" as well as in the historical record like Nazis using census data to find people with undesirable characteristics and murdering them (with IBM's help).
This is not far fetched conspiracy theory paranoia bate. It is factual events from reality.
If a company has a contract with an entity who pays them money for their services, it is literally in their interest to do it.