I'm not sure I'd go quite that far. The Culture novels are space opera, for example. yet they fall on the Enlightenment side of the divide; likewise for Star Trek, modulo a few more Romantic episodes and themes. Star Wars, however, is very, very Romantic, and it's probably the first thing that comes to mind for most people when you bring up space opera.
There's definitely a spectrum. I'm with you on the Culture, but I'm not sure I agree about Star Trek. If Star Trek is space opera, what qualifies as science fiction...?
Another month has passed and here is a new rationality quotes thread. The usual rules are: