My experience differs from yours. I caught lots of CC while retrieving hard bass baits.
"DIET: Channel catfish feed primarily on small fish, crustaceans (crayfish), clams and snails, aquatic insects and small mammals. There are even reports of channel catfish eating small birds."
https://www.fws.gov/fisheries/freshwater-fish-of-america/channel_catfish.htmlI think your situation may have been specific to CC that are fed routinely.