Yep. And at the risk of being called a "name dropper" I'll add Phil Nuyten, too. Inspired to greatness by Jules Verne and Walter Elias Disney.
Where would we be? Probably still diving. After all, there was The Creature from the Black Lagoon and Sea Hunt, too.
I got busted by the lifeguard at Farley Pool in Oakland for a surplus gas mask that I'd modified for skin diving and safety-pinned a latex Creature mask to the straps of. Think I was about seven, then. Been a water dog all my life. I'd be diving even if hydrophobia was a common human characteristic.
But yeah, Leagues was the big one for me as a kid. Before I became "The Creature of Lake Weatherbee" I pretended the dual eyepieces of that gray Navy gas mask were the windows of the Nautilus as I swam along the surface.
That was really a great time and place to grow up.