Well, as you know there are lots of kids, losers, toxic people in this game. You can simply block them in game but if you want to get rid of all then you can use the settings to turn off the chat completely. You might focus on your game better this way.
To get rid of chat simply click "Esc" and open settings then in Game settings go down with mouse wheel. You will see "chat box" click "hide chat frames" and done. Now you can just focus on your game. Read the map, Do your strategy. You don't need to see people crying or cursing you.