Using "reported" or telling people to report someone is bannable and considered harassment. Just report them and don't react to the comments. They are frustrating, but it's not really worth your time anyway. You had a bad game nothing you can do about it after the fact besides try to learn from the mistakes. People that tell you to uninstall or never play x champ are usually just tools. If you looked at their match history it's probably has plenty of bad games as well.
Play your game ignore the irrelevant comments. I had a Lee Sin game the other day, admittedly it has been a while since I've played lee so my first 10 minutes was not what I wanted. After getting first blood on the enemy jungler I over reached a couple of times and got picked off because my lanes were losing and I was trying to invade (mistake on my part). Two of our players started trash talking and bitching. After the 10 minute mark I started making better plays ignoring the harassment and helped to ensure my team won the game by keeping the enemies fed renekton off our EZ. We won the game and I had a good scoreline considering my start I reported him for harassment and got instant feedback he received punishment. Had I tilted I would have not righted my ship and played my game. We would have lost and whether he was punished or not I would have been frustrated over the loss.
Online gaming has always had this problem people trash talking and insulting each other. The words have changed, but the intent is the same. They are trying to make themselves feel better by hurting others. They don't have the strength of self to just play and enjoy themselves. They are mad most of the time when they play because they tie their self worth into the video game.
