GURPS Space question

[David Johnston2]

Originally Posted by awesomenessofme1

I'm not sure you understand what I said. It doesn't improve habitability. As written, Very Dense plus Marginal (Low Oxygen) gives 1/4 hab points, while Very Dense plus no Marginal gives 2/4, despite the former being objectively better for human habitation.

But it isn't. You're right, I forgot that if it didn't have Low Oxygen then it would be Habitability 2. So because it has Low Oxygen...it's still Habitability 2. It's not objectively better because with or without Low Oxygen the amount of nitrogen in your lungs is still lethal.