I see the supposed rejection of ROTJ’s ‘happily ever after’ as more of a reaction to ROTJ than anything else. People seem to have forgotten what a disappointment that film was, not just to many fans but to folks who were involved in the films. I’m pretty sure that’s why the comics had Luke turn to the Dark Side in the 90s
He didn’t turn to the dark side. He delved into the dark side in order to learn its secrets, to know why Vader turned and to conquer it from within. There’s a difference.