[Assumptions]How Simon ended up in PATHOS-2

[Googolplex]

The player has no HUD and runs out of breath when running, which makes little to no sense as he shouldn't be able to breath anyway. Is the lack of HUD a deliberate choice to minimise screen clutter?

No HUD means perfect immersion. I always love it when games do without any HUD elements, because HUD always looks ugly on the screen and destroys the atmosphere. There's also no HUD needed and I wouldn't call it "a lack". Rather I'm very happy about a developer like Frictional Games who make games without HUD.

I don't need and I don't want any feedback information. In real life I also don't see my health bars.

HUD always reminds me to play a game and prevent me to focus on a believable in-game experience.