I feel the same bro, it's amazing how Sally's method of raising him literally makes him lesser than an animal as a living being. Leave him in the wild and I doubt he can with the even compete bottom rung predator and scavengers due to his physical deformity.
There's no place for him in human society either. He got no desirable talent/trait to contribute to society, he got the worst personality a person could ever have, and he has violent, deviant and predatory tendency. He's certainly unfortunate to be born retarded but there's a ton of people in worse position than him that makes something out of themselves because they know their limit and simply trying to do their best to contribute. Meanwhile this sub-human goblin thinks that he is a polymath prodigy and master manipulator that has never been wrong in his life and refuse to do 'low level' job.