The "Only Up" comparisons from two separate players is a strong signal that the core concept really landed — that game has a devoted fanbase so the comparison is earned. Infinite Hack's little brother repeatedly falling off just to hear the death sound is honestly the highest possible compliment for a sound effect! The dynamic map building itself through random spawns is a genuinely creative mechanic that Sleeping Colossus and IntelligentGene both appreciated. The main thing to address post-jam is syncing the spawn timer more tightly to player movement speed so there's always something new arriving just as you reach the next platform — redkoala64's suggestion about avoiding spawns at lower levels is also worth implementing to keep the focus on upward progress. A downloadable version as JGgamess suggested would also help with the heavy loading time from the 3D mesh physics!
Feel free to check out my sky platformer too if you get a moment!