My thing is...on paper, was this the return of Luke Skywalker I would've hoped to see? No.
But given how it was setup in TFA, I think it was kind of the inevitable route to go and Johnson simply capitalized on the dramatic potential of giving him a huge arc.
If Luke was simply a bit reluctant to train her, but then snaps out of it and is wise and powerful Luke by the end of Act 1, it does kind of beg the question why wouldn't have intervened in TFA. By showing that he had taken his failure with Ben so hard and he had become so disillusioned with the Jedi's failures as a whole that he'd actually cut himself off from The Force, it both made sense of his absence in TFA and gave him a big emotional journey to take in this film.
So yeah, I totally get why a lot of fans weren't happy with the direction, but I really think this was the honest and logical progression from TFA. There had to be a significant reason for him to be missing in that film, otherwise it would've just felt like he was a cheap MacGuffin/cliffhanger. I now accept how he was treated in TFA because this film didn't shy away from why he went to the most secluded place in the galaxy, and gave me something rich and dramatic out of it. If we were going to be just getting a straight forward Obi-Wan version of Luke, there was no reason to write him out of TFA. He should've been there from the start if that were the case. That film sets up a lot of mystery around Luke, and this film gives us the hard answers.
I still have the OT if I want to see the pure, young and idealistic Luke. But, we're being told a story where a lot of bad stuff went down since we last saw our heroes and the victories of the OT have basically been undone, so it is what it is. That was a difficult premise for me to get past initially too, but I've accepted it. What I always loved about Luke Skywalker was he was a human being to me. Not a superhero. I feel like in this film we got to see both Luke the flawed man and then ultimately Luke the legend that I wanted to see when I first heard the ST was getting made. Didn't play out the way I would've initially wanted or expected, but a pretty bold creative choice that I admire. For me it was one of those "I got what I needed, not what I wanted" type of deals. I think that's a storyteller's job ultimately, otherwise it can feel a bit like fan fiction.