Too many commentators chose to begin their critique of the Mueller hearing by expressing disappointment in his theatrical performance. This set the tone for everything that followed, and the magnitude of what had just happened was diminished.
What took place was exactly what Mueller promised. Colleagues who know Mueller’s work have repeatedly reported that he never was the big talker in the room. And for many years admiration for his integrity, professionalism, competence, and truthfulness has been trumpeted by republicans and democrats alike.
Mueller made it clear at the start he did not want to testify. He was satisfied for his report to speak for itself. So the fact that his age might have caused some hesitation in his voice was totally immaterial. One of the sad consequences of this age of television imagery is that moments of serious business are too often seen and evaluated through a theatrical filter.