In Saskatchewan its illegal for big-game including bear. Un-ethical is a different topic, for some species using anything other than a solid is unethical. In countries where solids are used routinely for the biggest animals, they are also used for animals that aren't so big, shot angles that couldn't be made any other way, second shots on animals that seldom go down on the first shot, reduceing damage on diminutive critters, and reduceing damage on down but not yet out animals.
I'm sure that most of the soft-point only laws were enacted to stop people from flinging surplus hard-point around the game fields because it was the cheapest thing around, and for the most part that's good sense. Outlawing non expanding bullets completely, presupposes that everyone is an idiot and that there aren't special uses for special bullets.