The reason chat restriction is silly...
...is because limiting the messages of a toxic chatter simple forces the player to be more concise, biting, and even extreme with his argumentation (insulting).
When another player is getting on a chat restricted rager's nerves they do not have the available messages to communicate leisurely and offer specific rebuttles... Instead they are compelled to "verbally annihilate" the person with the few messages that they are allotted.
Alternative: make chat restriction have ZERO messages allowed. Problem solved.