During my years in the Army in the 70s and 80s, the EMP threat was to the transistors in our radios and whatever is the modern equivalent in computers, cell phones & etc. we were told to pull our radios out of their racks and turn them off if we got warning that a nuke strike was imminent.
We were also told that radios and similar equipment with old fashioned vacuum tubes were not affected by EMP when a nuke went off because of the older technology.
The geometries of modern silicon are getting smaller and smaller so it seems that it would require a higher frequency to affect the gate of the transistor or substrate or whatever is damaged in an EMP. But I am not a chip designer. But it seems like modern electronics would be less susceptible for many reasons.
However, if I were going to design an EMP device, I would design something that is targeted vs a brute force blast.
This is where a directed EMP device might be affective — aim it at an incoming missile, drone, etc. to affect its nav system or other electronics.