wrong
1) they didn't kill the Ayleids because they believed in human superiority, they killed them because the Ayleids were enslaving man.
Its called "The Alessian Slave Rebellion" for a reason.
2) the Empire that killed the Ayleids is not the same Empire that we see in Skyrim..
the Ayleids were killed during the First Empire (aka the Alessian Empire).
in the 4th Era, its the Third Empire (I say it should be the fourth, but all refernces claim its still the 3rd...)