Is that considered as a self defense?

Don't put your hands on people.

Guy is 3 times his size Slapped him silly with little effort Reached for small guys gun as he drew for defense, who he could easily over power Would YOU fear for your life? Clean shoot

I’m glad they shot his fatass

It was until the point he shot him on the back as he was trying to flee

Yeah, I’d say that’s self-defense.

Once big dude started running away, the threat was over. Every shot as he ran away was dirty.

Self defense He was hit He drew to prevent being hit again and the attacker went for the weapon This is clear cut self defense

First shot maybe. The shots in the back as he was running away, no. That's not going to look good in court.

Deadly force is only permissible if the person has probable cause to believe the suspect poses a significant threat of death or serious physical injury to the person or others. Big guy is leaving, no threat at that point, person shooting him should be arrested.

The response is more interesting than the video. The people who have a problem with the aggressor getting shot instinctively side with violent/lawless people and dislike consequences.