Per https://steamcommunity.com/app/475190/discussions/0/2999920878441544387/ :
The issue seems to be that the game runs faulty code when it detects certain CPU features (SHA1 instruction support) which are present in Intel's 10th gen CPUs and above*. Unfortunately, there is no compatibility setting to disable this feature, so the only way is to patch the executable yourself. Though maybe with this sale the devs are more interested in fixing up this game (Chris mentioned his worry about games stopping to work in their recent video after all).
Here's how to patch the game, copied from a different thread:
"This gets a bit technical, but don't worry, you can't break anything. You can always re-download the game after all. Grab yourself some Hex Editor and open up the Games Executable. Locate the 4 bytes at offsets 99F183 to 99F186, they should be "48 8D 46 40" and replace them with "90 90 90 90". Save the changes and try running the game again."