Robert Heinlein wrote on the same subject. But with a difference: marriages were decided based on a person's family history of longevity. People with a background of long-lived ancestors married others with the same history. The goal was to gradually increase the life spans of descendants. But when descendants began to live to be close to 500 years, they lost touch with those who lived the normal life spans because they no longer had mutual interests and the "long lifers" became a different group of humans. How could anyone 400+ years old relate to short-lived people?

How well do 90-year-old people emotionally relate to teenagers? There is no mutual frame of reference. The "long lifers" became like gods to everyone else. Many of them even saw the majority of humans as being "less than", the Other. And many of them no longer found joy in life and wanted their lives to end. A few, though, wanted to live past 500 years of age. The novel was called "To sail beyond the sunset"- I think but it was years ago when I read it and not being a "long lifer", my memory isn't what it used to be. Even at my current age, I know I wouldn't want to live to be 125 years or longer; it's hard enough to find relevance with much younger people. I don't want to lose all touch with the things that make me human by becoming a different type of human.

No surprise Musk, et al, see themselves as better than us "poor" people. To them, we're poor because we're stupid. Which is a great irony, considering that Musk was born into wealth and watched as his father worked the miners in his emerald mine to the point of death.

Born with a silver spoon in his mouth, in South Africa under apartheid, Musk didn't earn his wealth on his own. He used his pocket full of emeralds, made several good business decisions by buying the work of others and expected his workers to put in the hours and labor his father's miners did.