The way I see it, Palpatine was not discussing the hilt. At this point in time, Vader and Luke were basically the only two people in the entire galaxy who had lightsabers, so far as that movie was concerned back in 1983. in that sense, they were very much alike.

In the script, this is foreshadowing that Luke and Vader are gonna fight again. In the narrative, it's Palpatine taunting Luke about his father.

I won't say there is no valid insight in your analysis, but I will say that it's a shallow insight based on a common misconception. Try not to take Lucas' statement that Luke is the fairytale hero of the OT too literal.

Luke is the hero of the OT only in the sense that we follow his story more than we do anyone else. Luke isn't the hero of the OT because Luke isn't a hero.

The people who believe he is the hero who fights the empire with his lightsaber and wins are all wrong. He never once saved the galaxy with his lightsaber, and never came close to doing so.

That was also Rian Johnson's misconception in trying to subvert the character. No one who actually understood Luke had a problem with him not being the ultimate Jedi in The Last Jedi.

I went into that theater fully expecting Luke to die in that film. I also expected him to impart wisdom to his pupil, so that she could go on and perhaps do what Luke failed to do in the OT. She had the potential to be the hero that he never was.

The weakness in Rian Johnson's film is that he seemed unable to establish who the hero was supposed to be. He wanted Rey to be the hero, but Luke was the one who ended up learning all the philosophical lessons that he had already learned in the OT.

This left Rey out of any legitimate connection to many SW fans. She didn't have to learn anything to do what she needed to do, because Luke had reestablished his role as the pupil in the movie that was not supposed to be about his story. He was scheduled to die at the end.

If you follow TESB, Luke fails every test Yoda gives him. George is using the character the audience relates to most in order to teach the audience lessons. In The Last Jedi, I try to watch that movie as if Rey is the person I'm supposed to identify with the most, but I can't because that movie wasn't about telling a story. It was about shooting a film that had very little to do with the 7 movies that precede it.