The folks of Ordinary Adventures attempted to conduct an experiment to find out, and filmed the whole thing. Watch the video below and see what happens.
So, they knew that there was no game over state for the ride, that you couldn't crash the Falcon or die, but they were surprised to learn how much Smugglers Run is actually pre-programmed and apparently it doesn't really matter that much what you do or not. Sure, you'll hit fewer things if you pilot well, take on less damage and earn more credits, but not much else changes.
Is it a disappointment? Well, yes and no. Yes, because riders want to have the illusion that THEY really pilot the Millenium Falcon and make sure that it is their push on the light-speed button that is responsible of entering into hyperspace. And no, because in fact, even if a big part of the ride is programmed you still really pilot the Falcon, fire the guns, enter in light-speed mode when you decide it ( as long as you don't wait too long to push the button ), etc... So, yes, what you will do will definitely have an effect on the ride - hey, you can have the Falcon hitting anything you want if you steer the ship insanely!
Now, why did they programmed the ride so it works by itself if no one does anything? Well, first, chances are low that riders don't do anything when they'll get into the cockpit - after all that's what the ride is all about: having the illusion that you pilot the Millenium Falcon, so you're not going to wait in line hours just to don't do anything once you're at last inside the cockpit, right? Now, they could have programmed the ride so it stops if no one is doing anything, but they didn't do it. Personally i think that in this case riders should have a warning of Hondo Ohnaka - who assist riders all along the ride - with his voice saying that "if you don't control the ship it will have to go back to Batuu", etc... and after a few seconds, then the ride would stop. At least there will be a logic. But, again, as i've said, 99% of riders will do the job they're supposed to do, whether they are pilot, gunners or engineers, so no one will experiment disappointment or, if can say, will see the trick.
