The original trilogy made a huge deal about dark/light.
The Prequels made less of a huge deal about it I think...it showed Jedi like Qui Gon who acted in his own self interest and against the Jedi when he chose...or Yoda who comes off a bit cowardly imho for choosing exile when it was completely up in the air about what would happen with Luke/Leia but whatever. Sifo Dias creating the clone army. Dooku and Palps being Sith Lords in like line-of-sight to the Jedi temple and them being clueless....
They showed a more pragmatic view of the Force I think-- one that balanced the Individual User's ability with their amount of force ability.
The OT showed IMO that the Force was all that really mattered and Luke was pretty much just a vessel for it's re-balancing.
The Sequel Trilogy I think kind of doubles down on the OT interpretation of the Force (so far)-- Rey is a nobody who is seemingly possessed by the Force.
I think Luke's "jedi must end" comes from him seeing Jedi/Sith as two sides of the same coin - and maybe the Force is too powerful to be wielded by anyone without actually losing themselves to it's will.