When I look at whether or not Mega-Sableye deserves a ban, the first thing I look at is the usage rates. Mega sableye is not common in tournaments, as was noted earlier in the thread. Furthermore, its not that common in OU itself, being 29th in usage rates. From there, I looked at the pokemon with higher usage rates, seeing whether or not they "countered" Sableye. Of the top 20, I'd say around 7, maybe 9 at most have good matchups versus Sableye. I see that as Sableye being not broken or centralizing enough to deserve a ban. If sableye was as auto-win as people make it out to be, it should have a higher usage rate, or a higher rate of pokemon that counter it in use.
Furthermore, the idea that banning sableye will make the tier more varied is flawed. Sure, a sableye ban will let a couple new pokemon into the tier, but that's not additional diversity. If we banned every single OU mon from OU, we'd have a lot more "diversity", according to that logic. When a ban is made, you lose a pokemon. A pokemon that is expressly overcentralizing will add far more pokemon to the tier than Sableye's ban would, in my opinion.
I think that people are hung up on keeping a metagame the same as it was. Naturally, hazards were strong against stall in earlier gens or metagames. But, just like balance got better stallbreakers between gens in Zard Y and medi and the like, stall will get some new tools to combat strategies that once worked against them.
Furthermore, the idea that banning sableye will make the tier more varied is flawed. Sure, a sableye ban will let a couple new pokemon into the tier, but that's not additional diversity. If we banned every single OU mon from OU, we'd have a lot more "diversity", according to that logic. When a ban is made, you lose a pokemon. A pokemon that is expressly overcentralizing will add far more pokemon to the tier than Sableye's ban would, in my opinion.
I think that people are hung up on keeping a metagame the same as it was. Naturally, hazards were strong against stall in earlier gens or metagames. But, just like balance got better stallbreakers between gens in Zard Y and medi and the like, stall will get some new tools to combat strategies that once worked against them.