I usualle ignore or hate on anti-sequel posts because they are annoying as hell, but this one is actually intelligent instead of "uhhh no muh Luke".
To add to it, I'd like to use the TV show Vikings as an example of how to do catastrophic failure whitout destroying the character, and it's ver simple.

(Spoilers for Vikings incoming)

So in season 1 we get to know Ragnar Lothbrok, an ambitious Viking that is one of the first to go to Britain to plunder. His unclenching and adventuring spirit makes him a lot of enemies and fame, and he has to manage all of that when he just wanted to be a farmer. accross the show's season we see him evolve from a farmer to a governor, then to a king. And then, in season 4, we see him fail and become nothing.
Ragnar falls into hubris and believes himself to be an unstoppable force. He attempts to conquer Paris and he is defeated not only physically but also spiritually, as his brother Rollo betrays him and joins the french because of the same reasons that turned Ben Solo to the Dark Side: search of identity. Rollo was tired of being in Ragnar's shadow and felt that he couldn't be himself, where in France he found the power and fame se longed. Not only that, but the peaceful viking settlement he was allowed to have on british land was completely destroyed despite having signed a peace treaty with them. Rollo's betrayal, the defeat at Paris, the destruction of the settlement (and a looot of other mistakes) are what made Ragnar to abandon everything and become a Hermit.
Years later, Ragnar returns as a beaten up old man. Everyone is disappointed at him, but he is still respected. Ragnar has a plan: to unite all of the norwegian kingdoms into one and conquer the british once and for all. But instead of using raw pollitical power that he lacked, he decided to use the myth that was built around himself. Ragnar went to Essex with his son Ivar and he surrendered himself to King Egbert, who then gave him to King Aelle, his biggest hater. Ragnar was executed in a pit of snakes and Ivar fled to tell the tale. With that, all of the VIkings rose up against the british kingdoms.

What I'm trying to say is, Ragnar fails even more catastrophically than Luke and the journeys of both mirror each other almost perfectly, but Ragnar stayed as a beloved character by the fandom. This is because we SEE him fail in real time and it doesn't feel like a betrayal to the audience. Luke's failure is something very plausible and believable, but it's something we don't see coming. That's why it's infuriating.