It’s not about self defense. As long as you match, and don’t exceed the aggressor’s energy, you’re within your rights. If someone punches you, you can punch back but you can’t pile drive the guy, but you can hit back just as hard.
The punch the FedEx driver threw wasn’t meant to be fatal and was an acceptable retaliation after being verbally abused, then physically assaulted. It’s not his fault the aggressor was glass Joe.
Who the hell even uses that site anymore?