This game will never be a sport...
I read in a Riot interview that they intend for League of Legends to become a sporting event and reach the same level as football/soccer. I can assure you that this is never going to happen because the players of sports do not continually shout death threats at each other while an incompetent corporate developer continues to mess around with stuff.
Part of the reason sports, Tennis, Football, etc have stood the test of time is because there are set, clearly defined rules that players need to abide by. Making the game accessible for new players and old veterans alike. League has none of this as Riot continually change the game every season to resemble something totally different from the last season and there is no actual consistency.
They continually run the game through power "cycles" where one specific champion type is dominant before being knocked down hard. As is with this season which has seen a huge rise in marksman in lanes other then bot. Once the assassin rework is released, the assassins that have been tuned with the same power creep that the marksman have will be knocked off the top spot.
Traditional Sports and Games do not change their rules every year in order to increase appeal. They use a tried and true formula that remains constant (the rules of chess, for example have existed for almost 900 years in its current form). This is why League of Legends will never achieve the level of traditional sports and Riot are frankly arrogant for believing that.
Plus, nobody really wants to play a game where 9/10 players that get a kill on you are arrogant jerks about it. I have barely met ANY good players on this game, like I have on Overwatch or SMITE which seem to have more laid back communities. Most people in this game, if they get a kill would rather be cocky and say "Ez" then actually saying "I was lucky" or "Wow, that was close". You know, just to make the enemy FEEL better about possibly losing the game.
You do not see people playing amateur at any sport, beating each other up over a mistake or going "haha" to the enemy. (Except Boxing)