It’s weird because I ahead always thought that Luke would be the unconventional Jedi that would walk away from the dogmatic Jedi Order from the past. Guess I was wrong, and he followed the Jedi just like those who came before him, and Rey is now what Luke was.
Except that Luke does the opposite when we reach the end of his arc. He accepts that the old way has come time to go away with the scene with Yoda, and he reaffirms what the Jedi are about when he saves the Resistance and his friends. It’s also the greatest act of epic pacifism that we have seen in all of Star Wars.
So he basically did the exact same thing he did in the end of RotJ in a more badass way?
I would say this film is sending a similar message yet not retreading or backtracking in his character development. In RotJ, it’s about Luke and how he sees his father, normally someone who a son would look towards as an example. It’s about Luke learning to believe in someone.
TLJ is about Luke dealing with the struggles of what it means to be a master/teacher, and about believing in himself, which was a lesson he still needed to fully learn from the ESB scene where he can’t lift the x-wing due to lack of faith in himself.
EDIT: TLDR - Rotj is Luke learning to believe in others despite their flaws. TLJ is Luke learning to believe in himself despite his mistakes.