EMP is for the nerdy conspiracy theory crowd, not any one that understands science.
I’m pretty good on understanding the potential of thermonuclear dual wave Compton effects, as well as the sociological aspects of EMP-caused disruption.
That might make me a bit nerdy, but hardly a conspiracy nut.
It’s not so much that EVERYTHING gets fried, but rather enough things, particularly the controls for long line electrical distribution (i.e. the grid) get fried, and then social order as we know it breaks down quickly in the absence of electric power and all that is enabled by it..
It’s plausible, not conspiratorial.