This game is not the most optimised, that’s for sure :P But I just ran the itch exe on my laptop and it barely got warmer, even on the highest settings.
After some googling, I found other people experiencing high temperatures in the unity games, but that was 4 years ago, and apparently capping the max fps in the GPU settings helped a little.
If you are willing to give it a try, then on itch should be this game’s older version, v0.12 Debug, maybe running it will provide more info on the issue.