Good point. But this stuff is always cat and mouse. The mafia bigshots figured out that they couldn't talk on the phone in the 60s and 70s once the FBI started aggressively pursuing wiretaps. So they shifted.
In the 2000s, drug dealers figured out that Nextel direct connect weren't tracable... so Nextel kiosks sprung up in the hood and you'd see them all over. After that, prepaid burners were the next thing, followed by BlackBerry, etc.
If your organizing protests in such a way that are going to attract surveillance, "Use X" is dumb advice. It depends on the situation and what consequences you can sustain. An activist may want to be arrested. A Federal employee may sacrifice their career just for being present. Context matters, but the smart path is to leave your phone at home.
