That's not true.
During Beta prior to them implementing fuel you could fly to another system but nothing was there - you needed to "tell" the game you had left the old system by means of supercruise. (Transition)
Even now there are transitions:
- Normal to/from Supercruise actually is a transition from local space to supercruise space.
- There is a system (not sure which) that is close enough to fly on with fuel tanks. Someone on the forums tried it and nothing was at the destination. They had to supercruise (ergo: transitions)
The galaxy is not 1 smooth large space that you fly about in .. it's huge boxes you supercruise between. (As it was in Elite)
Supercruise != hyperspace. A hyperspace jump is indeed a loading screen, but this has nothing to do with planetary landing.