At the very least, a passing score on an online test would be a step in the right direction. It would ensure that boat operators have read through the boater operation manual and are competent enough to pass the test.
Proof of test completion would have to be presented during routine safety checks on the water, and be a requirement for anyone entering a bass tournament. Failure to comply would result in fines, penalties, etc.
Florida offers one, and it's good for life once you pass it. I believe some resorts require you to possess one regardless of age if you plan on renting a boat.