You have to hand it to Serling, Roddenberry an Stefano--they created better sci-fi on a shoestring, than others did with better tech, bigger budgets and better acceptance of the subject matter by the public, for many years after.
Sometimes there was an honest effort. When Trek got popular inthe 70's, a few network shows tried to emulate the format, and writers like DC Fontana, David Gerrold and even Harlan Ellison were hired to pen some good SF. Logan's Run was a nice try, but their scripts were watered down by the producers or the network. The Fantastic Journey was also another good shot at quality SF. But budgets seemed even smaller in the 70's (even at it's cheapest, Trek didn't look as crude as Logan's Run). However, once Star Wars appeared, intelligence went right back out the window and Glen Larson took over.
And is calling Wild Wild West, sci-fi, accurate?
I know they had gadgets and a few sci-fi concepts thrown in, but c'mon it's a western with some high tech spy nods.
It works as a fantasy, if not sci-fi. And I still hold to the opinion that Twilight Zone was primarily a fantasy series with sci-fi episodes in the mix. It was still a "magical stuff happens" series.
But that was my point--nothing before it or 20 years after it, topped it. IMO.
So you know, I am not disagreeing with you at all. I was just saying the list of choices for American sci-fi in general was longer than you suggested. But I'm with ya.