Their devs revel in people (players) getting frustrated because of overpowered heroes - laugh at it - and then when people want to leave matches, they complain about it. You can't have it both ways, folks.
Overwatch was designed to be a friendly game, and now they introduce killing as the only objective. Real smart. Will increase hate and frustration and ghastliness in the game. Basically every change they make will increase the rage quits and the trolls in games.
2 junkrat concussion mines -- bad idea
riptire speed boost -- bad idea, should be about 10%
fusion driver increase -- bad idea
barrier increase -- bad idea
move while healing -- good idea
damage reduced while healing -- bad idea
widow maker venom mine -- bad idea
reduced cooldown on grapple -- bad idea, but it was too long.
doomfist -- bad idea in itself
new symmetra since december 2016 -- was a terribly bad idea and basically most people now want her removed form the game or something similar. There are more and more calls for her removal now.
so they on the one hand introduce changes always based on player pressure, by the way, they do nothing of their own accord, that will increase the unfriendliness in the game, and then when people decide staying in a game is not to their best interest, they try to crack down on it harder and ban more people.
So on the one hand they do everything to make people more ghastly, and then they try to prevent that from happening by punishing, which will make them even more ghastly.
Good going Blizzard! Within a year basically and you have already sent your most lauded game ever to the ranks of Diablo 3 and current day WoW!!!.