There’s a lot of speculation that Luke will die. If that’s the case, it’s like the writers saw Game Of Thrones was making money and went “That’s making money, let’s do that with Star Wars.”
The thing is, people don’t go to Star Wars to see Game Of Thrones. They go to Star Wars to see Star Wars. If anything, TLJ should mirror TESB. Which is the ONLY Star Wars movie which no major character dies in. (Except maybe AOTC, But one could argue Shmi’s death was a major part of the movie)
And killing Luke IMMEDIATELY after killing Han is literally overkill. There is storytelling, and then there’s killing a character for the sake of killing a character. And killing Luke would be the latter.