Hmm, definitely a decent concept, but felt very underwhelming to me unfortunately. I like these single-button games as they can show a lot of creativity in trying to make a very complex game out of a very simple control scheme: it's definitely a noble goal as a lot of games should try to minimize control complexity whenever possible. And in some ways, I felt like the whole shooting/aiming mechanic being on a single button was interesting.
But for me, the game ultimately felt really annoying and clunky to me: instead of feeling genuinely challenging, it felt more like I was fighting against the game's own controls and only getting through obstacles by sheer trial-and-error. Jumping was inconsistent since it didn't look like there was any buffering or coyote time, the time-slow-down mechanic of shooting was annoying as it also inexplicably slowed down your forward momentum as well instead of keeping it consistent, the arrows seemed to awkwardly inherit character movement at times making them go off-target, and so on.
It's definitely not all bad or anything: I do think the concept is nice and the level design shows some nice creativity which made me want to keep trying, but it didn't last long for me. All in all, though, this is what game jams are all about: prototypes some concepts quickly to see how they end up, and I think this was a good experiment!