Mostly true.
I had the good fortune of being at The Monterey Bay Aquarium the day their Great White was put on display. Cute little critter. It was quite comfortable there for over six months, and I think it would still be there if it hadn't started acting like a shark...
I took my kid to Sea World once. He asked one of the experts there why they did not have a great white, and the response was "They don't do well in captivity. No one knows why, but they don't."
Did they put the great white in that big open ocean tank? With the big tuna and other pelagic fish? Did he start to eat his neighbors?