Ive played league since the release of quinn (season 3) and ive never been chat restricted, banned or otherwise punished. its pretty rare id say for someone whos played as long as me to never have a scuffle with the riot behavior squad. I acquired this restriction in a debacle between a fellow summoner and have learned from the experience a few things.
1. You must adopt C*ckold mentality. you are not allowed to defend yourself if someone flames you, especially flaming them back
2. You have to take it in the *ss with a smile and let them ruin your experience. talking back would ruin theirs! just let them get all the satisfaction.
3. Riot doesn't care who started it. you are both going to the principles office and getting sent home.
4. Muting wont stop them from inting because you wont ff.
Pretty fun let me tell you. Guess ill just not defend myself anymore... or go the T1 treatment and make a ton of accounts and try and ruin as many peoples day as possible. Only time will tell.
Edit: might come off as a complain post about me getting punished but im fine with my light sentencing its more about the question of standing up and whether its right or wrong to do so.
edit 2: just had another game where 3 people flamed each other i wasnt involved. basically lost the game because of it. no one got banned. why? 2 afks and 3 flamers. hows that different than my situation? the answer it isnt. its worse because someone afked and no punishment was delt.