First, what romanticism glosses over is whatever is dull, ordinary, or complicated. If you compare the romantic myth of the old west to the actual historical accounts, one thing you will notice is that the romantic myth is an absolute bloodblath compared to the historical accounts. The outbreaks of violence are played up to the point where there hardly seems to be anything else. What's played *down* is the ordinary day-to-day living that connected them.
Second, utopias rarely last in science fiction because science fiction is a very romantic genre, and utopias are so unromantic that few science-fiction writers will devote much time to describing them. This means that the utopia will likely be immediately attacked, or turn out to have some terrible flaw, or simply be kept offstage as the protagonist goes and has romantic adventures elsewhere.