I’m really just spitballing here, but I think maybe the problem people have with Luke’s actions in TLJ is that there has been this Superman-like mistique set up around him by our culture. People assumed (or inferred), because Return of the Jedi ended on a high note for him, that he essentially could or would become the ST’s Qui-Gon Jinn or Ben Kenobi.
It is because TLJ turned around and said “Nope. Actually, he’s had a severe crisis of faith. Whatever you wanted him to do, he’s having none of it.” And so it’s as if Superman is suddenly not for truth and justice (and the “American way”). He’s not what we expected. He’s Bizzaro-Luke.
Humanizing him in this way cuts people deep, I think, because of how we as a culture built him up as a sort of superhero in the 80’s. Whether or not someone read the EU novels.
You are combining what I see as two different ideas. There is the idea that Luke was set up as a legendary figure like Superman. And there is the idea that he was a good guy who would go on to continue to learn and grow.
I hate the idea that Luke is known far and wide for his various deeds. I like the idea that not many people knew what happened on the second Death Star, don’t know his parentage, and lots of people don’t believe in the Force. If anything, I think Luke would never really receive great recognition.
Seeing him fall is more like seeing your dad after 35 years and he’s kind of a drunk loser. He wasn’t one before and maybe you idolized him a bit, but c’mon.
I think most people experience a discovery that their parents are more human than they knew as children. That has nothing to do with a change in the parents.
Finding out that Luke isn’t a legend and still isn’t perfect is a great way to go about this. Making him a “bizarro Luke” is a different thing.
So for me, it’s far less about idolizing Luke than wanting to see him follow a path of growth and discovery, as I want for any protagonist I like.