Quote from Darkey on the 10th of June 2016:
Don't even think you could do a ban phase at this point in the games life. If you have 2 bans per team that leaves what 17 heros in total. How many of those remaining would be actually viable picks leaves a very small pool of heros to choose from.
Ideally if any hero is that broken it should just be banned by the event organiser.
If they would do a ban it would have to be 1 from a category but even then it be janky