Where does a 900 pound gorilla sleep? Anywhere s/he wants to.
Note, this is about email. Bottom line: if you’re using an email server hosted somewhere other than in your own home, you CAN NOT expect privacy.
It takes an hour to set up a Postfix server. It can run in a virtual instance on a Linux laptop sitting on your desk if you want it to. The email is 100% your property. No one’s going to “take a look” or otherwise scan it for information for government or advertisers. There are dozens of websites that walk you through the process.
Technology can be daunting, but it’s not out of reach for anyone.