If new things to be expert in proliferate faster than you can become an expert then life-span extension will not work. You would need to duplicate yourself each time there is a new thing you want to pursue. One you would be a concert violinist and the other you could cure the common cold.
> "you would need to duplicate yourself each time there is a new thing you want to pursue"
Much easier than inventing a duplicator is to imagine you have done this already, and the duplicates are all the other people in the world, busy being concert violinists and working on cold vaccines. What a relief to find that you no longer have to bother with such things.
