Love them or hate them there are a lot of common tropes across the science fiction genre. What are some of your favorite and least favorite tropes?
I think it goes without saying that one of the least favorite tropes is Deux ex Machina. I couldn't quite put my finger on it at first, but after watching the German TV show "Dark" I was utterly dissatisfied with it. The entire series up until the very last episode is about this inescapable time loop and alternative universes which is pretty cool while watching it, but then you get closer and closer to the end wondering how they are going to solve this impossible problem. Then surprise they just do it instantly in the last episode.
Another trope I am not very fond of is nanotechnology where there are trillions of tiny robots that can effectively act as magic. It just feels like a lazy way to write science fiction because you really want a fantasy.
A trope I do actually like despite how overdone it is, is the idea of a precursor or forerunner. It often brings to light the absolutely massive scale of the universe which I find fun to think about.
You just see less of each planet when you're boldly going where no one has gone before. On first contact, the chance of only meeting one culture is higher, since you're only talking to one group. If you talked to two cultures of the same species, it'd be more like second contact. That's why the Cerritos sees more of each culture than the Enterprise. Captain Freeman witnessed a political revolution on humanity's first visit to Pakled Planet. Captain Janeway only found out about political division among the Q after humanity had known Q for a while. And Worf got involved in a conservative religious movement on Risa. You've gotta know the mold before you can buck the mold.
Deep Space Nine stayed in the same place for 7 seasons, so there was TONS of interaction with the same cultures again and again. That's why we got to see their diversity.