SPY/SPY makes sense....like VPN honeypots....
Post# of 123676
makes sense....like VPN honeypots....it's a false sense of security...if you turn on Airplane Mode ....and you're not in the air....you must be trying to avoid surveillance....So they double down on collection.
If you get a VPN they know you're trying to hide, so they pat special attention to your traffic.The only solution, like you say : no phone. I bet even phones with the batteries removed (You are starting to see glued in batteries now) send data for a few hours with a hidden backup battery.
Of course now it's irrelevant for most people ....they are broadcasting from their bloodstream 24/7/365
Make a simple Faraday cage out of copper screen or leave phone at home and check for messages like the old days.