Finally watched it. I don't think it'll last. Maybe it is due to the Walking Dead, but I think post-apocolyptic shows need to be grimy and gritty and grotesque. This seems too neat and shiny. There is a disconnect between the aesthetic and the setting.
Yep. They go back to the 1880s, and everyone looks clean, all the clothes are new, yadda yadda yadda. Major disconnect.
Not saying it has to be The Road dirty, but it's way to sanitized.
You're assuming it's an EMP, but I don't think it is. They would have stated it, instead, they said they didn't know what happened. I think they'll match up the science (fiction) better than you're currently thinking.
JMHO
Not an EMP. EMP is one and done, that society didn't make any progress in 15 years signals to me that it's an ongoing event. Stout had it right - it's a fictional plot device. The only thing I could think of is a constant CME, but that wouldn't short out everything right away. Lots of electronics would still work.
Maybe some sort of fictional damping field where the little pendants create just enough of a disruption to allow electronics to work.
Cars - eh, you don't need gas. They can burn wood (no - seriously, they can), biodiesel, oil, so on and so forth. Plenty of fuels available. Even in an EMP, it wouldn't take long to retrofit some vehicles to function without computers.
I'll suspend belief and watch for the next few episodes and see if anything comes of it. It takes about 6-8 episodes for a show to get it's feet underneath it anyways.