One of Biden's greatest virtues was his appointment of qualified, competent, experienced and ethical staff and cabinet members. Chosen because they were qualified.
He never surrounded himself with incompetents who would never be able to steal his spotlight--and on whom he could cast blame if he himself made a mistake. He was willing to say "the buck stops here," because he knew how to be a team player, having served in Congress for decades.
If--and I say "if" because I haven't read and don't intend to read Tapper's book--he needed some backup he was well covered. His defense secretary was a respected retired general. His Attorney General was a District Court Justice with a sterling reputation. People leading medical departments had medical backgrounds. People in Labor had labor backgrounds, and not as lobbyists. His Secretary of Education had been commisioner of education in his home state. His much-maligned secretary of homeland security was a Cuban refugee who had been an assistant director of homeland security, a director of immigration, etc.
His VP had been the District Attorney of San Francisco, a major city, in 2004, when her successor was still a self-identified hillbilly.
In this situation, there was nothing to fear if he had a senior moment here and there. It wasn't a case of the blind leading the blind. As a team of ethical, experienced people who respected one another, we had nothing to fear. The government was in good hands.