Didn't make it to the end.
I like the idea that climbing a massive wall and reading other climbers' Epitaph. It delivers the lonely feeling. And making the gameplay and narrative fit to each other.
But the jump itself was too difficult to me, and I have to say the controls feel a bit werid to me. I make platformer sometimes so I do know how difficult tweaking these move are. But for a gamejam game which want to deliver a message, making it less difficult would be better I think.
Overall, I still like this game, nice work.