I can imagine someone saying "In a communist system we will all be slightly poorer because central planning doesn't work as well as markets, but it would be worth it because of the reduction in inequality"
Using Marxist terminology, that's not communism, that's mere socialism. Communism is pretty much defined by "To each according to his need".
"Imagine that by some unspecified magic we have solved that problem, so that everyone willingly pitches in to do their bit.
I don't see this anywhere in Xyrik's comment. I am not sure that at the time of writing it he was even aware of the incentives problem.
And once you start specifying elven magic as the reason a particular problem doesn't exist, you can't have any unsolvable problems because elven magic, done.
that's not communism, that's mere socialism. Communism is pretty much defined by "To each according to his need".
I'm not sure I understand your objection. I wasn't imagining anything other than an attempt at "To each according to his need". That might still leave many people poorer than under capitalism. (I said "all" but that was silly, and maybe that's the cause of any misunderstanding; I should have said something like "we will collectively be slightly poorer", which is what I actually meant.)
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?