I’m still pondering Rey’s experience in the Dark Side hole/cave. Luke seemed very wary of it. (Had he ever gone down there?) It was nothing like Luke’s experience on Dagobah. No phantasms appeared to her. It was nothing I expected at all.
Is the Force neither dark or light save for what you bring with you?
The way I interpreted that scene was Rey was tempted somewhat by the dark side due to thirst of knowledge or resolution regarding her parents. As if the dark side was lulling her into the void by promising her the answer she wanted since the other way with Luke wasn’t getting her closer. Her experience is still similar to Luke’s dark side cave experience; Vader’s helmet blows up to show a mirror image of Luke’s face, and Rey literally gets a mirror of herself on the wall.
But at the same time, Luke’s dark side cave interaction was much more clear that Luke was driven by impatience, which highlighted his recklessness that could corrupt him to the dark side much easier. Rey kinda just falls into it and… I don’t know, the whole sequence was weird as I can’t fully say for sure the reasons behind her were temptations of the dark side or mere curiosity that had nothing to do with the dark side. Maybe that’s the intention /shrug.