Two main issues:

1. The game gets exceptionally tedious by the end. Physics based platformers can be janky and are difficult to totally get down. This doesn't really succeed.

2. The main issue: This game has a deceptively, extremely depressing downer ending. It feels like a shock value fakeout like some edgy 2000s-era "let's trick a bunch of kids into watching this and traumatize them" drivel. I wouldn't have an issue with this if it wasn't hidden behind the facade of numerous hours of cutesy game about a squishy cat. It feels cheap and mean-spirited.