Why? Blaziken wasn't banned on Reborn in 5th, so why would it be in 6th? Megablaziken does the exact same thing. It even hits a little less, due to lack of Life Orb.
I'd be for no Mega Bans at all myself. Lucario gets killed by Aegislash, Khangaskhan...Why do people think it's op? It's pathetic speed and defenses are awesome. Aegislash can easily kill it. Mega Gengar...I've never had a problem with it tbh.