I always tell him he is being paranoid, because every app, especially the ones het finds important (like banking) encrypt their traffic. So who cares if the WiFi layer is encrypted or not.
For the people that do use WiFi away from home: It's easy to create an access-point that is malicious and has wpa2. Also, wpa2 isn't that great anymore, right?
I could tell him to just use a (trustworthy) free vpn (ie protonvpn, or just pay for mullvad) if he really needs to connect. That would take care of his concerns.
Am I wrong?