Riot is always concerned with toxicity at all levels of play, but their primary focus right now is finishing the League Client Update. Once it goes from Beta to Release they'll have the resources to focus on new features and the Behavior Initiatives, though I can't say where their initial priorities will be.
People may say to just mute the others, but that's just ignoring the problem and pretending that people aren't being toxic.
There is no way to punish a player in the middle of a match, so Muting is for your personal and immediate benefit. Yes, it's "ignoring" the problem, but that is how you make the match at hand more enjoyable for yourself and it isn't meant to solve anything permanently. Reporting is what you use to address the bigger picture and reduce that individual's toxic footprint in the future so that others don't also have to Mute them.
Riot got rid of the Tribunal, which I think was a good way for players to help with reports
The Tribunal was actually notoriously slow at handling cases (we're talking months) while the Instant Feedback System processes a case within 15 minutes. The IFS is also consistent with (when all IFS cases were manually reviewed) a false positive rate of 1:6000; better than the Tribunal had because players would vote inconsistently for fun or just to net their IP bonus.
Riot has mentioned that if/when the Tribunal were to return, it would be to accentuate the IFS for fringe cases, not replace anything. A new Honor Initiative would likely also be a part of it.
No, I've never been reported
I'm not saying you've been negative/toxic, but nobody knows if they are reported or not, you get no indication of it until you're punished.
But even trying to act polite and being nice doesn't seem to work
It's natural for a stranger to not want the unsolicited advice of another complete stranger, and even if you're nice about or a higher rank or w/e it that doesn't mean they feel your ideas are better than theirs; you might both be right, you might both be wrong. If they are not receptive, it's best to just let them be.
As long as your reports are accurate, just rely on them even if you feel they don't help, because they will contribute. Most players are not considered "toxic", but do have bad days and are more negative than usual. This can add up when multiple players are being just a little negative and it makes the whole match feel toxic, so encourage them to focus on the game and keep using Mute if they would rather argue.
