I don't disagree that in general blanket statements are to be avoided, and in fact, you're points are well-taken. However, I suspect we can agree that in an ideal world it would happen as you outline, but we don't live in an ideal world, and there's little chance of limiting collection to juveniles, QT'd in-country, etc. It's not a realistic expectation in many of these countries, and that's why I feel the way I do about CB's.
BAR began with an eye toward sustainability, and respect for the animals we all enjoy, and I don't think wild importation of this particular species fits those goals. I also know that because we don't live in an ideal world that CB's will continue to be imported haphazardly, and most will die.