voice chat?

i was thinking the other day "wow alot of people die while typing something out" then it dawned on me...add voice chat along with typing.think of it people will work as a team much better cuz of voice communication. LCS has it so why cant we solo Q players. people will fight less because actually talking over the mic and yelling at someone is way too spaghetti for this community. yelling over the mic is for counter strike gamers. dota also has voice. i dont see a down side to it. please list down sides if u can think of any please.