I knew of a sensei who taught Aikido when he was 80- he had white hair, wrinkled skin, and was barely 5 feet tall. Yet, he was one of the greatest martial artists the world has ever known. This frail looking old man taught almost a million people at the time of his death. In case you haven't figured it out yet, the old, wrinkled person of whom I speak is Morihei Ueshiba.
If you judged O-sensei by looks alone, I doubt you could find much respect for him.