It had nothing to do with the microphone. If the mike fed the tv feed for 80 million people then the mike was not the issue. Perhaps it was the speaker system in the auditorium.
The reason why Trump lost is because he was not prepared. He has no positions on foreign policy, domestic policy, energy issues, Veteran issues, education, nor anything else of importance to the American public.
He’s a bully, a liar, someone who actually lives in his own fantasy of greatness, and clearly unqualified as leader of the free world.