Correct me if I'm wrong, but did they not care because Austrians were seen as just another type of Germans until the mid-twentieth century?
So in a way an Austrian leading Germany would have been no different to a Bavarian or Prussian leading Germany.
/u/kieslowskifan has previously answered
/u/Georgy_K_Zhukov has previously answered How did Hitler, an Austrian, dark haired man convince the German people that the Nordic race was superior?