You were punished for your consistent verbal abuse and harassment against other players in your game, not because you were only defending yourself. You tend to rage at players who are playing poorly, demand reports against them and telling them to refund skins and champions if they did not perform to your expectations. This was abuse carried across the three chatlogs that were supplied to you when your suspension was issued. Before the permanent suspension hit your account, you went through multiple chat restrictions and a two week suspension for the same behavior. The punishment on your account is more than justified.
In regards to your self defense claim, you can still be punished for firing back at another players. When it comes to your suspension it only matters what you do, not what others do. While you may feel that you are in the right defending yourself or others, two wrongs never make a right. If you run into players displaying negative or toxic behavior in game you can mute them and report them at the end of the game. The moment you fire back with your own negative behavior you warrant any reports made against you and justify any disciplinary actions take against your account.
