Time for someone to make and sell a 'USB Killer Killer'
Upon detecting that a USB killer has been inserted the USB Killer Killer quietly disconnects its protected USB link to the PC's USB port.
It then flashes a rotating red LED, sounds a warning siren and declares thermonuclear war on the unsuspecting USB killer by way of its 1.21kV capacitor bank, which interestingly happens to be around the size of an overweight adult hedgehog.
Unexpectedly the USB killers plastic casing instantly explodes and showers the user in molten hot plastic and metal shrapnel.
Hm.. i should probably rethink this idea.
Actually no, if you're stupid enough to use a USB killer this is what you get.