A man can dream!
Probably not a major consideration for lemurs, bushbabies, and tarsiers.
Once again, we have nails because our ancestors had them. They evolved tens of millions of years before the first tools were made. Tool use was not a consideration in their evolution.
The function of a nail is different to a claw.
The claw is an aid in gripping to surfaces and holding prey in place or a weapon altogether.
The nail is there to protect your fingertips (or in some mammals it turned completely into a hoof) and as a tool to hold or pull small things (splinter) that would not be possible to do with claws.
Just think of the things we do and touch with our hands and the fingers attached to them, some of those activities or places where they touch - I certainly wouldn’t wanted claws anywhere near there.
I always wonder how that East Indian guy grew the world’s longest fingernails. He must have had somebody do everything for him. Mine break off all the time.
In fact, I think that was the point of the exercise: By growing such long nails, he’s proving that he has people to do things for him. It’s a status symbol.
And while tools didn’t drive the evolution of fingernails, it’s possible that our pre-existing fingernails were one of the traits that enabled us to become the premier tool-users on the planet.
OTOH, I have a friend, about my age, comfortably (financially) retired, who is growing claws to rival Howard Hughes’s legendary talons. He’s become horribly depressed in recent years, and I think he’s simply not taking care of himself. (There’s much other evidence of that too.)
Actually, I read somewhere that being in the Guinness is a very popular hobby in India. Maybe status plays into it as well.