Overwatch, like most multiplayer competitive games, has a troll problem. Whether it's people on the opposite team deliberately targeting you, or someone on your own team not pulling their weight just to spite you, or even just abusing you in chat, there are plenty of people who get their kicks not from playing the game themselves, but in making it less fun for others.
Those people are asses and Blizzard is constantly trying to push them out of the game, or at the very least to play together. One effort to try and move nice players together and keep the trolls in a corner by themselves, is the new endorsement system. Players are able to award others with points for social play at the end of a game. It can be for making great plays for the team, communicating well, or just being courteous and respectful. Those points add up over time and can give other players an idea of how social a gamer you are.
Better yet, those kinds of players can be matched together long term to create much more friendly gaming experiences for those who want it, as per Kotaku. Indeed, Overwatch's second new feature, LFG or looking for groups, makes it possible to find players who want to play certain roles. No more fighting over who's who, and if you don't mind playing anything you can select that to be matched more often.
With a minimum endorsement level system when looking for new groups -- making it hard for trolls to get into the nice matchmaking queues -- the role system and a new reporting tool, Overwatch should gradually become a much nicer game to play with nicer people to play with.
Although some trolls will slip through the gaps, the fact that friends can't endorse one another will certainly help stem the tide.