Asking players to report is useless, also negative.
If you report a player in a game once, it creates a flag which can lead to a review for their behavior in that game, Therefore you only ever need one report, the report you make.
Wasting your time /allchatting about reporting people, tilting your team; revealing your tilt to the other team does nothing for you but create disadvantages. Also if you rant too much you might have commited something reportable for youself.
In my opinion: It just creates a bad atmosphere in the game, all this whining about who should be reported: more than half of it is completely nonsense anyway, because usually people just want their team reported for feeding because they lost. But it's just a lot of negativity and anger which are the things you're way more likely to be suspended and banned for than going 0/10.
So bascially; If you think somebody should be reported, just report them after the game and don't talk about it. Multiple reports do nothing!!!