And one possible explanation (which the movie hints at but doesn’t state) is that Luke could have uncovered some lost skills. The force ghosts could have as well. Luke has access to the ancient texts. How? This is the first Jedi Temple. We never heard of that before. It is a given that every new story could introduce new aspects that we haven’t seen before. We get new planets. Why isn’t anyone asking why we’ve never been to Crait before? It might have been convenient at some point. What made TLJ for me was the new things. That seems to be what ruined it for others.