Currently you cannot report "bad behaviour", that requires some kind of item to do. Blocking the person does not help others, it just makes it invisible for yourself.
Implementing a system where everyone has 1-5 "report tickets" per month, and players who get reported by multiple people get automatically muted in said chat for a certain time, or until a GM/CM reviews chatlogs would be a better system.
If people try to abuse the report system, like for example reporting others for not valid reasons, they get penalized by having their "report tickets" removed for a certain amount of time, or premanently depending what the person has done.
Currently we can already "like" someones "good" input, so why not be able to report report the "bad"?