“Faking it” is the antithesis of authentic leadership. Following this advice is the most likely path to failure as a leader. You cannot act like a leader until you go through the hard steps of developing yourself from within.
With the visible failures of leaders who tried to fake it, people have developed sensitive “sniff tests” and can quickly identify who is authentic and who is not. If you fake leadership, people will be unwilling to follow your lead and will resent your attempts to exert power over them.