But yeah I can't speak for everyone because no one shoots the same, but for me I'm absolutely 100% positive that a .357magnum with the right load even factory loads, I can kill a deer or a grizzly bear by that matter, at 1 to 100 yards max for me with the right shot.
The only thing that I can understand why people say it won't is because there either a bad shot, or they have a bigger bored gun and think its better than everyone else's gun.