I think it started when Zeratul got his last major rework. It's necessary to report people...
Play with chat off till you get some good mmr in the game mode you want to participate in.
Honestly you'll have a better time and if you actually get muted then it is really easy to proof since you can't even see chat to begin with.
If i get ranked or unranked games where nobody plays a support or tank on purpose, my chat is off and i just make the best of it what doesn't mean it's a loss.