is turning off the phone except when needed to use it, and any communication on those phone should assume the conversations are being monitored.

That is interesting since VPN will definitely giving you a different IP address through DHCP, and you can even get a static IP address through VPN's such as NORD VPN. If you use a public wifi plus a VPN it would be interesting to understand how they would do this through a public router?

That being said, if big brother is comprising a list of people, they should already have that list if you have a government phone, so there is not much one can do about that.

The waves reflect off of you and other surfaces in the room and can be measured to "see" you.

only use it in a location you are comfortable in, and assume you are being monitored.

The WIFI signal from the router radiates out as a wave - just like light from a light bulb. Just like a light can illuminate you, the signal does the same. You could have no phone on you and potentially still be tracked.

is you specifically?

door handles when someone approaches, and some faraday case block those handles from opening, with a button emblem on the outside of the case to manually press the unlock button.

Like the idea that data can be read by monitoring hard drive lights. Good luck with that.