It's certainly visually interesting and has some nice elements to it such as a cool (if a bit suspect) boss fight as well as decent platforming, but it didn't really leave me hungry for more from the full game.
For one, the paint mechanic seemed a bit underbaked. While it was certainly neat to see an invisible world come to light through paint splatters, it rarely added much to the game apart from visual pizazz: for every level, all you need to do is just spam double jump and bam, everything's painted and you're just left with a very basic platformer. It's basically just smoke and mirrors: apart from a few occasions where you need to use paint as a bit of a scouting tool, in the end it just felt like busy work before we can actually play.
Apart from the paint mechanic, I wasn't really seeing any hints of other potential abilities, or anything else for that matter that intrigued me and got me thinking about what the later levels could be, since it already felt like levels were just repeating themselves now in this very demo: just paint everything, jump past few spikes, bounce on a few dudes here and there, repeat ad nauseum with minor token shuffling of those elements to try and make the levels feel different.
I still had an alright time playing it, but for a demo, I just felt like it didn't hook me enough to consider getting the full game.