The airwaves can only be jambed, not shut down. I cannot see the feds actually interfering with all frequencies across the entire 48 states and stopping individuals with batteries/generators and radios from talking.
If our power grid(s) goes down it will only be a matter of hours until the internet starts to fade. If an EMP impacts the power grid, then expect that so many internet routers will be toast.
I keep my ham gear in a shielded cabinet and disconnected from any wires just so I can use it when the event occurs. I believe it’s just a matter of time and with O the time got much closer.