An Army Travels on Its Stomach
The key to space colonization is solving the food issue. Star Trek solved it with magic bullshit: Replicators.
Most space fiction doesn't address it at all. I do remember reading one book where space travel to Mars had a line about having to eat their way to shower access because every possible inch of the ship was used as food storage.
This oversight in the current fiction of the Earthbound Human is a serious barrier to space development. Humans wrote stories about going to the moon for hundreds of years before we actually did it.
Popular fiction is a platform for collective development of important ideas. Star Trek is the source of modern cell phones and automatic sliding doors, among other things.
My understanding is Sun Tzu's Art of War made some effort to tell political to leaders "Hey, STOOPID, you need to FEED your military. Duh!"
And that's here on Earth where it's relatively easy to sustain life. Out in the barrens of space, you better have food, water and air figured the fuck out.
You need that more desperately than you need to figure out better propulsion methods.
Sorry, no, Elon "retard" Musk who was FORCED by the courts to buy Twitter after shooting his mouth off in public (probably while drunk or high) and then flushed eighty percent of its value down the toilet is not likely to get us to Mars with his hobby of blowing up space ships for weirdo funsies.
Maybe "uneducated savages" in Africa will get us there by solving food supply issues in very distressed areas. But billionaires dreaming of owning people someplace beyond the law of Earthbound Humans are just mentally masturbating, not solving critical issues essential to laying the groundwork for actually getting humans from Earth to Mars ALIVE and well with some hope of surviving once there.
Hint: First we need to pre-seed Mars with plant life long before a human tries to set foot on Mars and our fiction mostly doesn't talk about how the hell we will eat on Mars or get to the point of being ABLE to eat on Mars.
No, we are too busy being enamored of cool tech to wonder about boring details like not starving to death.