So, just to be clear, Luke’s character as established in the OT is: wide-eyed and whiny farmboy who magically destroys the Death Star, which leads him to train with Yoda, but he abandons said training after learning some Force tricks in a vain attempt to save his friends and create the future, which backfires and plays right into the hands of his father (who is also the most evil person in the galaxy — ok, 2nd most evil), and only after literally cutting off his hand to escape capture by said evil father, does Luke return for the rest of his training, which leads to his cocky and hubristic plan to save Han from Jabba, giving him the hubris to think he can save his pure-evil father. And it works! What’s the lesson of the OT? Being a whiny brat pays off if you have magic script abilities!
But yeah, it’s totally inconceivable that the guy who was drowning in hubris at the end of Return of the Jedi would try to then go on and recreate the Jedi Order but be too distracted by said hubris to recognize that his protege nephew was turning evil. And it’s totally inconceivable that this crisis of faith would allow enough doubt and fear to seep in for the dark side to rear its head for a split-second, but in that split-second cause everything Luke had worked for to literally crash down around him. (This is called dramatic irony.)
And then it’s totally inconceivable that this complete inversion of fortune, brought about by nothing more than a momentary split-second slip in his self-control would cause an identity crisis with galactic ramifications, leading to Luke questioning his entire life, the purpose of the Jedi, and the Force. Maybe he might even decide that if he, the most powerful Jedi alive, was unable to stop the cycle of evil, a cycle that traces its roots back generations, and most notably when the Jedi Council failed to see the rise of the Empire right under their noses, that the Jedi were part of the problem, and that he, being the last Jedi alive, had a duty to ensure it faded into history, thus saving the galaxy from itself.
It’s like none of you even watched Star Wars. Just because the story on-screen isn’t what you wanted doesn’t mean it’s bad.
Oh, also, Luke’s wrong. His plan is wrong, his reasoning is wrong, his lost faith is wrong. He’s scared. He’s afraid. And he knows (say it with me) fear leads to the dark side. Instead of allowing that, he thinks the answer is to cut himself off and break the cycle. Welcome to the movie The Last Jedi, where everyone is wrong about everything they do and the journey of the film is to get everyone straight and thinking right again.
