No, the chat box exists because Riot put it there when they made the game for people to use how they want, and they obv don't want people abusing it so they made RULES that defined appropriate use of chat, and if you broke those RULES, then you got that PRIVILEGE revoked.
But now, with this system, its just a popularity system of who the larger community finds annoying.
At the end of the day it's Riots call as to what they allow people to do while using the chat, as much as you like think that you know what the chat is and isn't for, if tomorrow Riot decided that using the chat to discuss the game was inappropriate and started banning people for it, you have no choice but to stop playing the game or go along with it.
That's exctly why almost every company or game producer, or society itself provides RULES that define what good behavior is.
The term "toxic" is just a term used by people to paint behavior they don't LIKE as against the RULES.
Here's an example.
I have a chat server, and in my rules i have the condition, If your behavior is found to be "irksome" then you will be punished accordingly.
Who defines "irksome"? Well at the start I do, It's still not fair because I have the ability to bend the rules, and as a user you were never given a fair chance because its not a well defined rule. However, there is still a general agreement as to what irksome is because I have a close relationship with my users, so it flies for now.
But eventually my chat server gets big enough or I get lazy or greedy enough that I don;t want to hire an army of moderators, so i implement an automated bot to do my banning for me. Now who defines "irksome"? Well the bot does, and I happen to use the same bot Riot is using now. So what defines irksome is just by popular vote of the people using my servers, and now has close to nothing of what I originally thought of it as.
If enough sheltered and emotionally unstable people start using my server, people will start getting banned for saying things like "you're not supposed to do that" and "Hey can you please stop", because maybe people get really hurt when people ask them to do stuff, like gank a lane, or don;t troll, or stop being a jerk and insulting people.
Below is a transcript of the game that got me a 25 game chat restriction, and If i had already gotten one it would have landed me a 14 day suspension, because that's how the punishment system works now.
Game 1
DragonsDwell: i called mid
DragonsDwell: why
DragonsDwell: is this happening
DragonsDwell: i called mid and nobody even contested
DragonsDwell: you didnt even call it
DragonsDwell: after me
DragonsDwell: youre just in my lane
DragonsDwell: hello?
DragonsDwell: why
DragonsDwell: go top
DragonsDwell: nobody is top
DragonsDwell: i called mid
DragonsDwell: twice
DragonsDwell: and nobody said anything
DragonsDwell: oh
DragonsDwell: we have no jg
DragonsDwell: it would be nice if i got solo exp
DragonsDwell: so i can hit 6
DragonsDwell: and gank
DragonsDwell: like mid laner
DragonsDwell: would
DragonsDwell: and not be fucked
DragonsDwell: thank you
DragonsDwell: pls
DragonsDwell: please
DragonsDwell: i called mid
DragonsDwell: mid is a solo lane
DragonsDwell: can you pls go top
DragonsDwell: so i can not be behind on exp al lgame
DragonsDwell: please
DragonsDwell: why go mid if we have no jg
DragonsDwell: go top
DragonsDwell: i called mid
DragonsDwell: can you pls not go mid
DragonsDwell: can you not deny cannon minions
DragonsDwell: like wtf did i do
DragonsDwell: to make you angry at me
DragonsDwell: did you want mid
DragonsDwell: i would have swapped with you
DragonsDwell: in pregame
DragonsDwell: if yo usaid something
DragonsDwell: ??????
DragonsDwell: what kind of q was that
DragonsDwell: i jsut asked you to NOT take cannons
DragonsDwell: and you try to take it with your q again
DragonsDwell: STOP
DragonsDwell: maybe save your q for the dragon
DragonsDwell: jesus
DragonsDwell: no problem holding it to snipe cannons
DragonsDwell: go away
DragonsDwell: PLEASE
DragonsDwell: ez needs HELP
DragonsDwell: I DONT
DragonsDwell: HELP TOP
DragonsDwell: im tilted as fuck
DragonsDwell: dont even want to play right now
DragonsDwell: tbh
DragonsDwell: im down 2 levels on velkoz
DragonsDwell: with two kilsl and didnt miss a single minion
DragonsDwell: from backing
DragonsDwell: literally missed zero minions from backing and had two kills
DragonsDwell: and im down 2 levels
DragonsDwell: im ff at 15
DragonsDwell: and if you vote no im afk
DragonsDwell: i called mid
DragonsDwell: and this morg said nothing
DragonsDwell: i asked her to leave my lane nicely
DragonsDwell: and she just ignores me
DragonsDwell: literally wont even respond to me
DragonsDwell: this is so fuckign retarded
DragonsDwell: what the fuck did i do to you morg?
DragonsDwell: i dont join random games
DragonsDwell: and just fuck people over
DragonsDwell: i dont know
DragonsDwell: fro no reason
DragonsDwell: if thats your idea of fun
DragonsDwell: idk
DragonsDwell: congrats
DragonsDwell: im not our mid laner anymore
DragonsDwell: i give up
DragonsDwell: mrog leaches 9 min of exp
DragonsDwell: and then leaves
DragonsDwell: 4
DragonsDwell: icant hold mid
DragonsDwell: im not going top either
DragonsDwell: because we have no jungler
DragonsDwell: and i cant roam
DragonsDwell: cause of morg
DragonsDwell: taking my exp
DragonsDwell: same
DragonsDwell: nobody can help him because of this morg
DragonsDwell: could have laned with him
DragonsDwell: but instead laned with me
DragonsDwell: and made sure i cant help him
DragonsDwell: cause im alwasy down exp
DragonsDwell: k
DragonsDwell: jesus
DragonsDwell: like i wasnt mada at the start
DragonsDwell: iwas jsut vonfused
DragonsDwell: adn i asked you to leave
DragonsDwell: for the benifit
DragonsDwell: of the team
DragonsDwell: and you literally jsut put me on mute
DragonsDwell: or wont respond
DragonsDwell: thats fuckign toxic
DragonsDwell: icalled mid
DragonsDwell: and you ddint even say anything
DragonsDwell: i would have gladly swapped
DragonsDwell: with you
DragonsDwell: if you wanted mid
DragonsDwell: but you have to fuckign say asoemthing
DragonsDwell: i cant take smite
DragonsDwell: and go jg
DragonsDwell: once the game starts
DragonsDwell: you cant jsut show up in my lane
DragonsDwell: and say "fuck you"
DragonsDwell: and tell me to go top
DragonsDwell: wow
DragonsDwell: that velkzo is really far ahead
DragonsDwell: that sucks
DragonsDwell: wow so fun
DragonsDwell: im having fun right now
DragonsDwell: i tried to deal with this
DragonsDwell: im not gonna try anymore
DragonsDwell: its not worth the effort
DragonsDwell: this isnt ranked
DragonsDwell: idgaf if we win or lose
Who did i personally insult? Who did I harass? What racial slurs did I use? Did i encourage self harm? Did I threaten somebody? Did I go into the game with a negative attitude and say the game was over right from the start?
No, I called mid in pregame, nobody said anything about it, so I typically assumed it was fine, then this morg shows up in my lane, NEVER SAYS A WORD ALL GAME LONG, and just lanes mid with me, and uses smite to steal cannon minions. Refuses to communicate, and essentially makes sure the team loses and wastes everybody's time.
And because I tried to reason with her, and then gave up and declared it hopless, I get chat banned for negative attitude. Which is what the riot employee told me my ban was for when i asked him in my support ticket. Negative attitude, for at least trying to communicate with somebody who was very clearly trolling. If i had just not used chat and let this person ruin the game with out even trying to eke out a win I'd be in the clear, but because i WANTED to win, and i tried to use the CHAT to communicate with a TEAMMATE, I got banned. For "negative attitude".
If I had done this after coming out of a 14 day suspension I could have gotten my account PERMANENTLY BANNED. For the chat you just read above, PERMANENTLY BANNED. It's happened to people.
The system should change, but honestly it probably won't. because money