By what metric? In my opinion actually solving all of the problems we currently have and man we have a lot of them past the obvious ones like climate change, that would be our greatest achievement.
The optimistic thinking is that with thousands/millions of tireless 24/7 brains at work on these problems we could address more problems in biology, chemistry, physics, materials science, etc. faster. It's a bold, but not unreasonable belief.
But that’s not something actually actionable. This isn’t a plan, it’s pure hope that maybe potentially if we just put enough money and energy into this, it will just magically solve our problems. Call me a luddite but that’s a crazy amount of copium.
Lots of hope for sure. This is the biggest most expensive scientific endeavor in my lifetime. I can think of a lot worse things to spend the money/carbon on.