Tallguy said:

Going strictly by Star Wars, the Jedi Knights were around when Luke was born. Or at the latest shortly before. So since 1977 it's only been twenty-ish years between Luke's father's death and Star Wars. So it's not like this was a prequel thing. If anything you might argue that the fall of the Jedi was even LATER in Luke's lifetime.

Even if this is true, Star Wars does imply that even before the Empire started wiping out the Jedi, the Jedi rarely, if ever used The Force in public.