Neither did I. He seemed quite patient explaining everything. Maybe it's his brother?
To my ears, Brett talks with the cadence of a man who believes that the thing he's going to say in the following sentence is profound. It might be unintentional on his part, but that's what I hear. Tone and cadence matter in audio formats.
he talks the way he talks. Theatrics probably come from lecturing experience
That’s the impression I got too. Probably a matter of taste.