He did more than walk away from the old Jedi Order. He walked away completely from everything and everyone.
Because he is a flawed character who thought he was too dangerous to do any good. It’s kinda the necessary foundation for his character arc.
I’m almost willing to forgive the Luke tempted to kill Kylo flashback stuff, but what will still remain a head-scratcher to me is buying the idea that post Jedi Academy-Luke doing absolutely nothing, NOTHING, to use his time on the island to figure out a way to redeem Kylo or help in any capacity, especially when he hides little clues like a piece of the map of his location in R2D2. I feel like an ashamed Luke will guilt him into action; not “leave me to die” Luke.
He wanted to die because he felt like he failed in his ultimate purpose in life and what Yoda wanted of him. He lost faith in himself. And if the arc is about Luke learning to believe in himself again (which is a great arc) then he needs to lose faith in himself at one point and feel that he is better off staying away from everything. His speech about “Luke Skywalker, a legend” says this perfectly.
I’m struggling so much here because on paper, it sounds GREAT. But again, I can’t ignore little clues like leaving behind that map puzzle piece in R2D2 for someone to stumble upon it, like Rey, when the time was “right”. Leaving those clues sounds like TFA was setting up the Luke I was thinking of, the one that didn’t give up completely during isolation. If there was no clues left behind, then I would digest this easier, because on paper, I believe you’re right, if Luke felt he let down Yoda in rebuilding a new Jedi Order, then yeah, I guess he would give up everything. What’s your take on the map piece? How does it still work in the frame-work of TLJ?
From my understanding, the map was essentially to the first Jedi temple, where it was known by few that is the place where Luke was. Not a map left behind by Luke for others to follow.