You're moving goalposts. You literally said
> I fail to find anything in history that advanced the sciences or the arts through "collective effort of hundreds or thousands of humans".
> It's only for war or to consolidate power in the hands of the ruling class, never for the benefit of society at large.
I'm breaking it up into two statements because sufficient evidence has been provided to contradict the former, and some of your rebuttals did not align with the latter. Let's break those down:
> The moon landing is defintely a fruit of a war effort.
But is it only for war? Or did it "advance the sciences" + "for the benefit of society at large"?
> Wikipedia is the opposite of a top-down effort.
Your original statement didn't say it had to be a top-down effort. It's certainly "collective effort" + "not only for war" + "for the benefit of society at large".
> Aqueducts and railroads: responded on a sibling comment.
Scale and precision also matter and don't negate the fact that these are "something in history" + "collective effort" + "not only for war" + "for the benefit of society at large".
> LOTR films: I don't even know how it relates to the point, but it's funny that you cultural landmark that only worked because it's an adaptation of the works of a single individual.
I only picked LOTR films because they are notorious for being large scale and you never said it didn't have to be an adaptation. I could have picked The Simpsons, Star Wars, Breaking Bad, you name it.