In traditional societies like that of India, old people are accorded a lot of respect.
Is this well-deserved or a relic from the past?
I believe the 'tradition' of respecting one's elders is a relic from a time in our past when society was essentially agrarian.
If you think of how such a society functions, skills are handed from generation to generation — farmers' kids grow up to become farmers and carpenters' kids grow up to become carpenters, and so on . . .
In such a society, kids acquire their 'professional' skills from their fathers . . . so, obviously they need to 'respect' their elders as the elders are the ones with the 'knowledge.'
In the modern world, kids acquire their life skills in schools and colleges and make of their lives whatever they wish to by learning the necessary skills.
As far as the color of the hair goes, scientists can tell you about the technical reasons behind hair turning gray.
Black hair is black because of the melanin content in it. That chemical also determines the color of skin — so, you have people in the tropical countries whose skin tone is darker than people in the northern latitudes whose skin tone is lighter.
As people age, the hair coloring mechanism begins to falter with a build up of hydrogen peroxide in the hair root which leads to black hair turning gray — it has absolutely nothing to do with 'wisdom.'
I can think of 'wise' old men like S. Chandrasekhar and Albert Einstein and many others . . . but at the same time there have been such spectacularly young geniuses . . . from Beethoven and Mozart to Srinivas Ramanujun and many others.
Indeed, even if great scientists live to be 'old', their most important life work tends to be something that they would have done when young.
So, this business of respecting one's elders is way, way over the top.
Just one more meaningless relic from a bygone era that we need to jettison forthwith.