...you mean anything not in a metal box/cage right?

So basically anything important wouldn't be affected. Phones, cars, pcs, servers wouldn't get touched.

Besides all this is, basically an antenna on roids. You pull a couple mW with radio. A sudden gamma rays burst well shoot maybe a Gigawatt through your wires. That's what breaks your gear BTW.

So if you spread that wattage in a cage it well absorb it all and melt. everything inside would be fine.