A Khanate implies that they were strictly nomadic race of Man’ari Eredar. The government continued under Archimonde and Kil’jaeden. This government became strictly authoritarian and oligarchic Eredar Princes ruled over their respective fiefdoms aka Prince Jaraxxus and Prince Malchezaar etc. I would continue to describe this hierarchy as a dictatorship akin to a Fascist state as we see that the Demons still have societies and demonic hierarchies each controlling their regions of the universe/nether.
I hope we actually see Man’ari and the Burning Legion Remnant or something like that joining in the final hour to fight alongside the mortal races of the universe to stop the Void. The reason for the Burning Legion was not merely the galactic conquest and destruction of those who dare defy them and eliminate worlds touched by the Void. They exist to principally to destroy the Void at least that was Sargeras plan.