After finishing and getting all trinkets, three problems stop this from actually being good.
1. As others have noted, the controls are slippery, which is probably a poor choice for any game, least of all a precision platformer. It makes the graviton string portions and vertical looping sections particularly unpleasant since you have no vertical control and even less horizontal control as your acceleration in the air seems even lower than on the ground.
2. Snapping instantly from one screen to the next makes certain parts of the game artificially difficult. You don't really react to the visual input so much as muscle memory for these parts. The fact that the controls are slippery means you may have to start accelerating in anticipation of the next obstacles before you can even see them, or decelerating, and several times I made it through one screen and instantly died to a row of spikes at the same position on the next before the character was even on screen because it was still drifting.
3. Autoscrollers. These have also never been good, and it causes more annoying artificial difficulty due to often having to flip before the platform you are trying to reach is visible. So you just die the first time at several points until you know what's going to happen ahead of time.

It's a shame because some parts of the game are good, especially the music.

For a precision platformer the controls are really slippery. I don't agree with other reviews calling it outdated; I still find the main movement mechanic to be interesting, but it can never hide how annoying the character is to control

I lovvvvvve this game
best 2011 indoe game