Lorewise why would Orcs want to stop Garrosh?

[Redith]

He is bringing the orcs up in power, and changing their history for the better. Why change that? I understand why the Alliance and the rest of the horde want to stop him...but why the orcs?

[Lisaara]

Not every orc liked what Garrosh was doing. Garrosh brought the orcs to power but he did so like a tyrant and no orc was equal to Garrosh. Not every orc is a brute or a blood craving mongrel. Eitrigg and even Saurfang were disgusted with Garrosh. They have seen the horrors before and Garrosh was undoing everything Grom and Thrall had done for the orcs that gave them salvation from their bloodlust.

If our president(or whatever leader you may have) started going back to the old ways of segregation and hating on everyone but white men, would you still follow him even if he bring you, a white man, to power? Same concept.