Yep. And I believe Jimmy Olsen also originated in the radio series, just as, decades later, Harley Quinn originated in the 90s animated cartoon. And I honestly can't remember if my first exposure to Batman was via the comics or the old Adam West tv series, which I watched religiously as a kid, along with reruns of THE ADVENTURES OF SUPERMAN with George Reeves. And, growing up in the sixties, I knew about the Shadow and the Phantom and Mandrake and that bunch because my dad, who had been a fan back in the day, introduced me to them. (Heck, my grandfather gave me his old TARZAN hardcovers when I was a kid.)
The likes of Batman and Superman are so ingrained in western culture, for most people born from the 60's on wards it's going to be difficult to pin down when we were first exposed to their media.
For me I think it was a hardback Superman Annual/activity book type thing from the mid-80's and an old matchbox toy Batmobile (the Adam West one) that I inherited from one of my older brothers. I also have vague memories of a Spider-man cartoon in the 80's and a Tarzan TV show that was probably on Sundays on Channel 4 between repeats of the Adam West Batman show, Gentle Ben, Flipper, The Littlest Hobo & Black Beauty...Damn. It's weird what shakes loose when you wander off down memory lane.
Point being, I'm pretty sure I didn't read an actual super hero comic book (other than my friend's 2000ADs and a random issue of Eagle my grandfather got me once) until I was in my late teens, early twenties. And that was mostly out of curiosity of what all those shows were based on.
And it took 'John Carter' who inspired a lot of these characters (particularly Buck Rogers, Flash Gordon & by extension Star Wars as a whole) closer to a century to make it to the big screen!Meanwhile, somebody mentioned CONAN above. He first appeared in the pulps back in 1932, hit the comics in 1970, and finally made it to the big screen in 1982, some fifty years after he debuted in WEIRD TALES magazine!
It seems as is often the case, timing is a huge factor in whether or not something gets adapted. Carter was a little too ahead of his time while the later derivatives were right there in the zeitgeist.