This is pretty cool. For constructive criticism I thought of a couple of points maybe to help.
1) It feels like the way the cars move is quite random so when I die it feels more unfair rather than because I messed up if that makes sense. As a quick idea something like having different kinds of cars like a small blue one that always did smaller bounces and a large red truck that always did large bounces and a yellow taxi that always drove along the road etc. So the behaviour is more consistent which helps the player improve their skill over time.
2) For the coffee it wasn't entirely clear what the inventive was to get it, I think it makes me move faster for a little bit but I think it would be cool if it was clearer what it did. Or instead have it as another end state like I have a little caffeine energy bar and if I run out of caffeine in my system I would stop so I have to keep drinking the coffee to continue running.
I know time is super limited in a game jam but I just feel like it's better to receive at least some kind of constructive criticism on what could be better as I personally find that useful, so I hope it's not taken the wrong way at all haha :)