Jeff talked about this before release (they may feel different now) saying how little effort it would take to implement a hero/role limit and that it could happen. https://youtu.be/5eeHz0sDbM4?t=840

tl;dr - He said if it ever becomes so prevalent that it's the only thing players are doing he'd have concerns

After the last two ESL days, and the cluster it was, at times it wasn't even fun to watch. It was even on the boring side watching 2 tracer/winston/lucio on each side going at it. So they have options, maybe not same tank/healer stacking? And no more than 2 of each offensive/defensive heroes (TF2esque if you will) if they don't just make it HL1. But watching the Gosugamers weeklies are much more entertaining than ESL has been. At least IMO.

If it's true what the first reply says about them going to an HL1 for the rest of ESL I personally feel that's the correct choice. Just unfortunate for all the teams already eliminated.