That's true. But that would just be the breaks. Kind of like filling out your deer tag, then spying a Boone & Crockett record standing at the edge of the cornfield. Gotta let it go until next year. Or keep your powder dry until you find the record.
I have a friend who has caught a couple of Florida bass that might have threatened the state record, but in the lake where he was fishing, he had to release them immediately. That's just the price he pays for the abundance of PIGS.
About kids: The Dry Run Creek area below Norfork is popular with kids under 16, yet they have to release everything they catch. Wouldn't the hatchery area be a lot more interesting for nearly everyone if there were bigger fish to be caught there?
About barbless hooks: I'm one of those guys who loves to fish with crankbaits at night for browns. Just from my personal experience, it's a lot easier to remove barbless hooks from a fish in the middle of a dark, foggy night. (It's also a lot easier to remove them from my gloves, coat and fingers...) I'm pretty convinced that, overall, they do less damage to the fish I catch. But that's just anecdotal.
As for enforcement, other states -- Arkansas, for example -- have barbless regulations in place on some streams. At the very least, the MDC could talk to biologists and field agents in those states to get real data about the effectiveness and enforceability of those regulations.