I don't think Rey was more powerful than Luke in The Last Jedi. She won a physical fight with him. That’s all. There’s more to being a Jedi than that.

レイがルークより強いとは思えないわ
ルークに心理戦には勝ったけど、それだけよ
ジェダイになるにはもっと大事なものがあるわ