No but they can train a model to know everything about you and sell it.

They actually have precedence in that as it’s their legacy ad business.

I could absolutely see them getting more proactive with their ad business. Something like mortgage brokers want to know you executed an offer on a new home (high indication you will be shopping for a lender). Then that turn into, your employer wants to know you’re talking to other employers. Then of course there’s many more nefarious examples people would consider more invasive but may not even realize it leaked from their email provider.