I just watched the associated dev video And if I understand it, what the author is doing is kind of interesting.

The sensor to see a 3d scene is 2d(eye or camera). What is being done here is simulating a 3d sensor(for a 4d world) then we are looking at this 3d sensor using our 2d sensors (eyes). I don't know if this is the common way of rendering these 4d physics simulations. But it is the first I have heard it described this way. It is also why the narrative of the game focuses on eyes, because that is what it is doing.

https://www.youtube.com/watch?v=tKDMcLW9OnI

Reminds me a bit of a guy who created a functional virtual camera in Blender with lenses and film layers.

https://www.youtube.com/watch?v=YE9rEQAGpLw

I don't want to be the guy who has to use this level editor (although, in a similar way, doom was 2.5d, and so the level editor could essentially be 2d, so maybe it's not so bad?)

If this is 4d doom, i wonder what 4d quake could be