It makes sense. It was just poorly written and displayed on screen. Anakin choked his wife in the same movie. Anakin was not just a Jedi but a solider. He was also for the majority of the movie emotionally conflicted and confused.
Luke was also for the majority of ROTJ. He would have fallen just as quickly if he had accepted his fate. Instead seeing his father's hand was a great reminder to him of a path he did not want to go down. Anakin had no such reminder or help.