All four of you have valid points. Companion parrot breeding is really a double-edged sword. We can mentally separate ethical breeders from unethical ones. But in the real world it's nearly impossible to allow one group without allowing the other. I think there would need to be a major overhaul of our legislative and enforcement systems before there were any chance of achieving such a feat. Likewise, there's no efficacious method to educate the bird-buying public on which breeders are of quality and which are not. Perhaps we need an 'Angie's List' for bird breeders? But even then, how many folks would consult it? Not many, I'm afraid.
Speaking broadly, bird breeders are responsible for both proliferation of threatened species as well as flooding the planet with unwanted/abused birds. So there's no easy answer. Two things are for certain, though... 1) Threatened species become so mainly because of man's self-serving greed. And 2) unethical breeders thrive for the same reason.
Again, I think that each of you --Jean-Pierre, Renee', Rosalyn, and Helena-- have asserted some valid points.