There are basically three types of movies. Action, Drama and Comedy and yet one of the most versatile of genres, science fiction, is so heavily skewed towards action that when something comes out that isn't an action packed thriller people are upset. Even those comedies which come out in this genre are action movies with jokes, yet some of the best movies in the science fiction genre are dramas.
Is this simply another example of people assuming that "guy movies" have to have explosions and the assumption that "science fiction" is primarily for guys. I don't think that either of these stereotypes are true, but I also don't think that this is why they make most science fiction movie. I think there are a plethora of reasons which we can take one at a time.
1. The Star Wars Effect
Star Wars was one of the first huge science fiction blockbusters. It is primarily an action movie. (It's also primarily fantasy but that's a different argument). Since movie makers are more interested in emulating success than coming up with new ideas that may or may not work they reinvent Star Wars and typically they make a lot of money.
2. Expectations
The longer we have science fiction be an action movie genre the more people expect that and movie makers have to meet expectations or have a really good reason not to. This is why you can find independent science fiction films such as Donnie 
Darko and Primer which are excellent movies which are farther on the drama side of the equation than the action side.
3. depressing movie
People tend to want to escape into science fiction. This is where movies like Edward Scissorhands and Bicentennial man break down. These are reasonably good moves, but they also tend to make you want to cut your own wrists which doesn't make you want to watch them over and over again.
4. Action is Scifi is easier than in other genres
Part of this "problem" is that if you're going to make an action packed movie science fiction is a natural place to go. Movies like the matrix and independence day were able to be far bigger in their action because of the science fiction elements so if you want to make a summer blockbuster science fiction seems a natural choice not because you like science fiction but because it allows for you to have giant robots fighting other giant robots in the streets of new york.
5. Science fiction is expensive
Special effects cost money so if you're going to have robots, or spaceships you want to get your value out of them. Action movies draw bigger crowds to the theaters so you put in your big chase sequence and a couple fights to draw in the crowds.
There are certainly other reasons that science fiction falls on the action side rather than the drama side of movies most of the time, and I wouldn't want to cut down on the number of good science fiction action movies because I really like them, I just want to see a few more science fiction movies that don't have explosions and gun fights too.
Read More
Darko and Primer which are excellent movies which are farther on the drama side of the equation than the action side.
3. depressing movie
People tend to want to escape into science fiction. This is where movies like Edward Scissorhands and Bicentennial man break down. These are reasonably good moves, but they also tend to make you want to cut your own wrists which doesn't make you want to watch them over and over again.
4. Action is Scifi is easier than in other genres
Part of this "problem" is that if you're going to make an action packed movie science fiction is a natural place to go. Movies like the matrix and independence day were able to be far bigger in their action because of the science fiction elements so if you want to make a summer blockbuster science fiction seems a natural choice not because you like science fiction but because it allows for you to have giant robots fighting other giant robots in the streets of new york.
5. Science fiction is expensive
Special effects cost money so if you're going to have robots, or spaceships you want to get your value out of them. Action movies draw bigger crowds to the theaters so you put in your big chase sequence and a couple fights to draw in the crowds.
There are certainly other reasons that science fiction falls on the action side rather than the drama side of movies most of the time, and I wouldn't want to cut down on the number of good science fiction action movies because I really like them, I just want to see a few more science fiction movies that don't have explosions and gun fights too.