Honest heads up: the game never opened for me, so this rating reflects that rather than what you built, and I'd genuinely like to redo it if you get the loading sorted.
What happened: the screen sits on a pulsing dark red and never moves on. I waited, reloaded the page and waited again, same result both times.
I did see your note on the page: "IMPORTANT: sometimes the game doesn't open after the splash screen, if that happens reload and open again". So you already know about it. In my case the reload didn't help, which is worth knowing, because right now that bug blocks 100% of the players it happens to, and in a jam where people give each entry two minutes before moving on, that's votes you never get to earn. The build is also titled SKGJAM26'PROTOTYPE internally, so I appreciate this may be a very early stage.
What I can praise: flagging the problem yourself instead of letting players discover it is the right instinct, and "sanity as fuel" is an interesting hook. LAST HUMAN / SURVIVE / SANITY FUELING reads well as a premise and I was looking forward to it.
If you find the cause, reply here and I'll come back and re-rate properly. Also, "it'll stay playable for the rest of the world's life, and if itch dies I'll find other platforms" is a nice answer to the end of life question.