I know TLJ isn’t perfect, but I think the way it handled Luke felt very mythological to me.
I like to imagine an alternate reality where instead of George making a Star Wars trilogy, he adapted the legend of King Arthur into a trilogy. The trilogy ends with a happy ending, like ROTJ did. I guess Arthur becomes King, brings piece to Britain, and marries Guinevere. Something like that. A very typical fantasy, Happily Ever After, kind of story.
Now, obviously people would know what to expect if they know the text, but imagine most audiences didn’t, and they concluded the Arthur story decades later in another series of movies. Guinevere has a affair with Lancelot, Arthur hears a prophecy about a child born that would be the undoing of everything he loves, so he orders all babies born that day to be killed (What??? That’s so out-of-character for Arthur.), and eventually his own nephew Mordred, who survived the massacre, grows up to betray him, bring his kingdom to ruin, and Arthur fights him to the death. And the story ends with Camelot and the Round Table in ruins. I could imagine people saying, “Wow, I can’t believe they made Arthur sequels only to ruin their happy ending!”
I mean, Star Wars doesn’t have to be King Arthur, and doesn’t have to follow the same story beats, but the family tragedy that permeates the sequel trilogy definitely makes it feels more mythic to me. Even the stories of old didn’t make Arthur sinless, and I’m personally glad the Sequel Trilogy didn’t make Luke sinless either. I guess I relate to that, having made a lot of mistakes myself, but I understand others don’t.