You’re not. But using your own server means your flight itineraries, bank statements, utility bills, and Amazon receipts won’t be surveilled (by them, anyway),

You’re not. But using your own server means your flight itineraries, bank statements, utility bills, and Amazon receipts won’t be surveilled (by them, anyway), even if you occasionally send mail to GMail inboxes. If your enemy is Google, then that’s a significant win.