It’s more accurate to say that space doesn’t have a lot of easy access to external heat sources. Your local temperature is pretty much going to stay your local temperature without some significant effort being put into it. If you’re a rock, that’s cold. If you’re a spaceship full of humans and electronics that continually emit heat to operate, you’re going to stay pretty warm and shedding heat is an engineering problem that must be solved.
It’s more accurate to say that space doesn’t have a lot of easy access to external heat sources. Your local temperature is pretty much going to stay your local temperature without some significant effort being put into it. If you’re a rock, that’s cold. If you’re a spaceship full of humans and electronics that continually emit heat to operate, you’re going to stay pretty warm and shedding heat is an engineering problem that must be solved.