Actually, it pretty much goes back to "Superfriends". Aquaman had his own cartoon in the 60's in which he was no more lame than any other animated superhero in the 60's. (Hey, riding a giant seahorse is kinda cool, and he had Garth helping him out by way of contrast.)

Power-wise, pretty much everyone in "Superfriends" was reduced to the bare basics of what made them different (while generally speaking and acting the same as each other in all other ways). Batman and Robin were useless without their utility belts. Wonder Woman was a glorified cowgirl ("LASSOO ALL THE THINGS!"). I think I saw GL make a ring construct exactly once, and he had to announce it as if he were a magic user in Order of the Stick ("I'll use my Power Ring to create a helicopter!"). And of course, Hawkman flew.