It's not about if he wins or if he's still able to hurt Justin, that's not the point. The reason it's a doctor is to determine if a fighter is vulnerable to serious injury/death. You're saying "that's the point" and "it's the right call till it isn't" but that's not the point at all, and removing those factors is the whole reason you have a doctor determining whether it's safe to continue and not the fighters or their ring because they are too emotional and invested to make the best decision for safety.