I'll rest on that note.Captain Marvel (Shazam) outsold Superman significantly until Fawcett comics folded, and dc buried the character for decades because of it.
Superman WAS a big deal complete with TV shows and radio shows, but he had peers for sure.
but just for fun for the people who still think he was a-list back then. see if any old person you know can name the actor for the superman tv show back in the 40 or if they even remember watching it.
I'll give you B-list at best.