This is a guy who's sitting in a piece of technology that allows him not just to fly, but also to breathe in outer space, harness the power of light itself as a weapon, and travel to distant planets ... but he doesn't trust it to aim a torpedo? Hell, with their level of technology, they should have targeting systems that can pull off precision headshots from the other side of the galaxy. The ship's computer should be so much smarter than the pilot that when Luke tries to deactivate it, it'd merely shrug off the command. "You push all the buttons you want, monkey -- I'm gonna go ahead and complete the mission without you." Meanwhile, the antagonist in that scene is a former Jedi who is now "more machine than man" (machine = evil) and leads the technologically advanced empire to crush a small rebellion. The galaxy is saved not through strength of arms or martial skill, but by mystic mind tricks.
Though we can't help but notice the mystical Force did exactly f**k-all for Alderaan.
But Star Wars was simply following an old sword-and-sorcery trope. The Lords Of The Rings is particularly fervent in its anti-industrialist agenda, constantly equating nature, forests, and rural communities with good, while the bad guys build noisy assembly lines (and even use gunpowder, which is portrayed almost as a dirty trick). The most densely populated kingdoms are all being slowly corrupted from the inside, while the more rural areas remain untainted except by modern conquest.
New Line Cinema
Possibly because the good guys were too drunk to accomplish anything.