This is true -- but the example as given assumes no centrally managed economy. It's just a case of everyone independently deciding to maximize paperclips.
We have moved away from a complex allocation system to a simple one. It doesn't matter if you use money -- the relevant aspect of the situation is cooperation.
Of course, I may be reading to much into "everyone decides". But I'm assuming if they all 'decide' to do something because they have a gun to their head, then the downside is obvious.
How much money would it take to engineer biological immortality for at least half of the world's population, within 20 years, with 99% confidence?