It's sociopaths who should all be killed or otherwise removed from society.

Lots of sociopaths as the term is clinically defined live perfectly productive lives, often in high-stimulation, high-risk jobs that neurotypical people don't want to do like small aircraft piloting, serving in the special forces of their local military and so on. They don't learn well from bad experiences and they need a lot of stimulation to get a high, so those sorts of roles are ideal for them.

They don't need to be killed or removed from society, they need to be channelled into jobs where they can have fun and where their psychological resilience is an asset.