Riots way of Chat Restrictions.

I understand flaming in a league game is bad and that sometimes when you get into a really heated game and losing bad you say some stuff that riot notices as a bit too overboard and you get either a ban or a chat restrictions for being toxic, but why does riot punish just the person that was toxic, I feel if the person that was toxic was harrassed by other people then says something they should at least be punished too, its the same thing that happened with my chat restrictions and I find it unfair that people get to call me garbage and other mean words but when I respond in such ways it results in a chat ban because I came up with a good arguement, especially since in arurf you get stuck with a champ you either dont know how to play or with a champ that gets hard countered in lane, an entire game of arurf I kept getting pulled by blitz and rakan and blitz just cced me to death, after several deaths I started to get a bit annoyed so of course I said "this isnt even fair" and of course I got greeted with the usual "lmao your just garbage" which of course I state that im playing a higher skill capped champ but of course it never works with how people deal with these types of stuff, so im stuck in 20 minutes worth of harrassment and rude players while I cant say much because of the chance of me stating stuff can get me chat banned while they walk away with a fun time and with no trouble. This has happened to me twice and im a bit done with how this works, this time thankfully I didnt get chat restricted because I didnt say anything bad. I kind of reformed after my first chat restrict but people say stuff that makes me say something in return and it kinda bugs me alot,