I really liked the inverted temple run idea. Until I ran into hitbox perception issues. Thankfully there was a skip button. The hitboxes on level 2 were easier than level 1 because the shadows signaled how large the gaps were.
Because of the close to flat perspective, long gaps that existed when rocks scrolled by become smaller as they approach the horizon making it difficult to weave. This might be difficult to notice as the designer who knows how to get through the level but can be frustrating for new players.
If the perspective angle was made slightly steeper (closer to bird's eye view but not directly top down) this inverted run will still require some skill without having hitbox gauging struggles.
Nevertheless a great concept, really beautiful art & I liked the choice you made at the end to return the stars. What happens when you keep them?