I'll give the benefit of the doubt and assume that the microwave emitter is only activated by a kill-switch, but that just further begs the question of how the fuck any device with a powerful microwave emitter THAT ISN'T NEEDED TO FUNCTION AT ALL made it anywhere near the market. Let's not even mention the fact that the game's creator was somehow magically gifted at both software and hardware design, and apparently managed to slip ENTIRE MURDER FUNCTIONS past the entirety of the game's development team.
Like, all of this is just the tip of the shitberg that is SAO's writing, but it still amuses me how the entire thing falls apart in the very first episode.