I think it depends on the individual bird how they'd respond to clipping and if they "know" flight or don't. My amazon has always been clipped, and to our knowledge, never learned to fly. He has no concept of flight, but he does love going outside, riding in the car, coming out to run errands with me ext... and it would be far more cruel (at this point) to take away him coming out into the wider world than to flight him so he's stuck indoors. On the other side of the coin, my parents have 3 fully flighted birds who have always been flighted (except a brief period when I was a baby the cockatoo had to be clipped). They have never been outdoors outside of a cage, do not go "in public", hate the car, and their whole life is indoors. They are all talented fliers who love flying around the house every day. It would be beyond cruel to clip those birds.
It's a tough choice to make, but I venture to say, request the breeder doesn't clip and at least teach the bird how before you decide. It has always bothered me that Kiwi never learned but we didn't adopt him until he was 10 y/o and had no interest in learning, so we made the best of the situation by bringing him out a lot.