He was apparently qualified; after all he was born in the Ukraine and speaks the language. That alone would qualify many people. The problem is that he was a holdover from the 0bama regime and he remains loyal to it, not to the United States.
His chain of command knew he was a problem. Yet they did not remove him. They knew there were issues with leaks and unprofessional behavior and they did not remove him.
The entire chain should be fired.