Historically, competition is what drives humanity forward. For a utopia to be stable, it'll probably need homogeneity has well, which sort of defeats the purpose.
"Historically, cooperation is what drives humanity forward."
What I'm pretty sure about is that simplified-to-utter-uselessness statements are NOT what drives humanity forward. Lots of empty meaningless phrases here.
The competition theory of social organisation tries to stimulate this by creating artificial adversity through (typically non-violent) competition between people. I speculate that one of the key issues with this approach is that a lot of the problems that you create are not bounded by "underlying reality" as such - they emerge from the competition itself, and so we end up spending a lot of effort solving meta-problems which, if you stripped away the competition, aren't really "helpful".
Further, it seems difficult to distinguish which problems are "real" problems, and which aren't, because the competition does exist - what we end up with is a pervasive sense that a lot of what we're doing isn't useful, but we can't work out what or why.
Considering a post-scarcity world, it is not difficult to imagine a pseudo-utopia with the way technology is going. Using the example of Manna, imagine the ability to plug into some perfect VR world that looks and feels just like reality. Why would anyone want to "compete" in that scenario?
Already today, human beings would rather stay at home and consume various forms of media (tv, games, etc..) than go out and "compete." Humans typically value security over a marginal gain in luxury. Even the risk-takers among us err closer to the security-side of this spectrum on the whole.
I think those in this thread that worry that humans will always have an innate desire to one-up their brethren are worrying about nothing or some close approximation to nothing.
The best we could hope for in such a situation is that we realise the immediacy of the "real" problems, and start to focus on those, arresting the decline before it becomes too severe. I have an (unfounded) expectation that the process of switching our (i.e. humanity's) productive capacity to focus on the "real" problems would be characterised by cooperation rather than competition, because the adversity required for progress would already be there, and we wouldn't need competition to create it.
If humanity becomes more fragmented during that process (see the rise of the isolationist right around the world), then we would run the risk of that cooperation being focused on destructive goals - that would seem to me to be along the lines of the worst-case scenario.
It strikes me that a lot of that is my interpretation of some of what is in Joseph A. Tainter's "The Collapse of Complex Societies", which I saw recommended on here, and subsequently read. I heartily re-endorse the recommendation (I did a search to see if I could work out whose recommendation it was that pushed me to read it, but I'm afraid I can't work out which it might be, for which I apologise).
At the moment the most played video game seems to be League of Legends where player compete to accumulate gold through killing other players amongst other things. So the human instincts come out, just in the virtual world.
Maybe the future is humans merrilly killing in VR while peaceful robots look after them in the real world, a bit like a variation on The Matrix.
Can't really reproduce history, though. We've yet to see the extent what humanity can do if they work as one, but most practical and theoretical fields are advanced by competition more than cooperation. Mathematics is a global competition between universities, chemistry is a race to make industry more efficient and profitable, biology requires patents and being first to market to be viable. Physics actually seems cooperative to me, but I'm sure the more practical sub-fields: electronics, structures, energy etc are all driven by competition.
My point is not about anecdotal examples. The ones you provided merely prove that mankind can withstand competition to some degree. My point is that you are making a statement which is likely supported by your vision and its bias, but not by any scientific study.
It is interesting to note that a conflicting opinion could be supported by the same logic and different anecdotes.
I'd say it was more technology that did it. Chimps both compete and cooperate and don't advance much. It was the invention of writing, printing, electricity and the like that changed things.
Couldn't resist...