Is it?
If someone says "I am mid I don't give a f**k" and you report, what will it do? As far as I can tell the only stuff that gets punished right now is whatever is on Riot's "no no words" list.
We do penalize for a range of behaviors, not just use of language other players find offensive in chat. Can understand the skepticism on that. Hopefully the changes to report notifications we're just rolling out at present will help give better visibility and understanding of what's actually being dealt with how.