This poses one of the great ethical quandaries in animal rights.
On one hand, living in zoos, away from their natural communities and activities, is considered terrible for animals. It leads to the wild animal equivalences of mental illness and lead to shortened lifespans compared to their wild brethren who have a far more interesting social environment. And wolves are especially social creatures. Even being born and raised in captivity does not help much.
On the other, wild animals in captivity need not fear predators or starvation. For a rare or critically endangered species, the care of trained zoologists can be a bulwark against extinction. But if they can't breed in captivity or survive out of it, what is the gain?
Which side am I on? If you ask me, prepare for me to say I do not know.