Isn't it astonishing how our perception has changed with the years. I was 6 when this first aired, so I didn't watch it then, but even 10years later such programs seemed ok and "normal". But looking at it today makes it feel like a curiosity. Like the B movies SF of the time, that are mostly funny for us to watch now.
And we have to keep in mind, also such TV productions were basically low budget B movies. I guess the catering for one episode of GoT has cost more than a whole episode production of Twilight Zone.