While that's true, 'Star Wars' isn't bereft of intellectual debate, either.
The difference between the 2 movies is 'ALIEN' wears all of it's content up front. All the themes are presented to the viewer on screen. They range from the dangers, difficulties and hardship of space travel; the influence and power of Super corporate entities; plunging into the unknown and it's repurcussions. Along with other more mundane and prosaic issues like pay inequity and will the coffee be any good when we do start working in space.
Much of 'Star Wars' intellectual discourse is different. Good vs Evil is the obvious fundamental theme present on screen but the high end content is concealed beneath the surface. You don't see it. For example, much of the themes are based on Lucas' use of liberal use of material Joseph Campbell raises. You have to look externally beyond those movies to research the ideas Lucas was using as inspiration or come into the cinema with them 'on your sleeve' so to speak, in order to understand the Heroic Mythology that is present under the Saturday Morning bubblegum content of the movies.
As a result, 'ALIEN' has enjoyed it's intellectual discussions for different reasons. Being a very different movie, it's discussion will be far removed because in many ways, 'ALIEN' is the antithesis of 'Star Wars'. It's almost a polar opposite. Space travel is difficult, aliens do not liberally populate the galaxy like so many anthropomorphised cartoon characters in a Warner bros cartoon; and the pay rate sucks. Whereas 'Star Wars' is more concerned about playing 'cowboys and indians in space'.
That's not a bad thing - and I'm happy for it - but the content of both movies is so different it's not even comparable.