So where is this so called ‘Deep State’ that keeps extremists out of power and safeguards institutions?

It is running the nations of the world regardless of who is elected to whatever office. While it didn't like Trump Trump didn't do very much harm to the deep state. Thus Fauci and Birx were able to play him like a fiddle and look at the result. Bribedem is so demented the deep state doesn't even have to try.