The lack of incentives (which, I think, exists in Xyrik's scenario as the alternatives are... much less palatable)
Basically the idea is that everyone realizes that if we do this that we could vastly accelerate the speed at which we develop, and thus solve many of our problems such as over-population, food, etc. by spreading among the stars, after which people could once again live a more free life and create their own systems, including but not requiring a governing body.
Basically the idea is that everyone realizes that if we do this that we could vastly accelerate the speed at which we develop
This seems obviously, patently false to me.
Even if you have in mind a far-reaching remaking of humanity into enthusiastic slaves of some god-like entity, I don't think that it would either "vastly accelerate the speed" or would lead to "more free life" in the future.
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?