I'll be totally honest, I'm okay with the idea of Luke being a disillusioned bitter old man. Execution is the problem for me. And that probably stems from the quote from the article and that it wasn't an inspired story. If someone really wanted to tell the story of Luke being a bitter old person and how he gets his act together and finds the way back to the light I'm sure the outcome would have been much more credible. The thought process was probably more like "let's draft a list of what people would expect, do the opposite and try to fit something of a story around it".
This is where I am. I am ultimately okay with what was done with Luke-- but I fully agree there could have been better about it.
Just spitballing...
But say in TFA, right after leaving Jakku, the Falcon goes into autopilot. Dirch the 20 minute Rathar scene. Go directly to Maz's place, where Han is waiting, having been alerted his ship was finally activated after a decade. Get all the Han and Maz stuff done at the same time.
After Kylo takes Rey, instead of going to Leia, Han takes Finn to Luke. Luke can be the same bitter disillusioned dude he is in TLJ, blaming himself for what happened to Kylo Ben. He begrudgingly joins them as they then go to Leia-- and pick up with things as they are-- only with Luke grumbling in the background, and not going on the rescue mission.
After the battle turns poor for Poe, Luke hops in an X-Wing and goes to help, after Leia tells him he's being an ass. During the battle, he senses Kylo Ren, and lands. Then we get the end that Mark Hamill pitched-- that Luke shows up to save Han, but is too late. He does something heroic, lake maybe he takes out the base, so Rey can still face off against Kylo on her own.
You could then start TLJ in more or less the same place. Luke can still be apprehensive, but he doesn't need to spend 2/3 of the movie denying he can help. Maybe just the first act.