the animal-rghts activists suggested that "he would never have normal life" did they?

but of course he wouldn't! isn't this guy gonna live the rest of his life at the zoo or are the suggesting they will release him?

if so, i doubt that will work, a polar bear habituated to humans is a very dangerous animal. best he stay at the zoo.

in regards to other animals that have failed to live with their own kind jewr,
i guess again it depends on if you are talking about in a zoo environment or in the wild.

remember keiko the orca of "free willy" fame? he never managed to assimilate with a pod of wild orcas and eventually died in the wild.