The problem with this movie is why Luke has been written to do that wrong in the first place. And the more I think about it the more it comes to mind that the true problem is where TFA left Luke in the first place, and that wasn’t RJ’s decission clearly, but JJ Mistery Box Abrams.
He defined an arc for the trilogy where just for the sake of mistery and cliffhanging (which are as well marketing entertainment decissions) the true hero and protagonist of the OT was lost and locked in an island.
Actually it seems this has nothing to do with JJ. Something i was told a long time ago and the Art of TLJ seems to confirm this, is that the plot point of Luke retreating to the Old Jedi temple after kylo destroyed the new jedi order comes right out of George’s original treatment and long before a director was chosen. Kira (Rey) was to go in search of him and he was going to reluctantly train her. But this changed the second Harrison was on board and it changed to the search for Luke, who wouldn’t be found until the end. Again, this was all set in place before JJ was chosen as Director.