Remember, about 25% of men are partially red-green color blind. So, a 'fire engine red' such as in the usual banner at HN such men can see, but lots of 'red' in mixtures of colors register as black. An emerald green can be seen, but in lots of mixtures the greens don't register. So, some light greens register as gray.
Mainly it makes him look color-blind, and used to people not designing accessible visual experiences.
The fact that he found the site difficult to read (like everyone else), he attributed to the most likely cause of such experiences in the past, i.e. his color-blindness, rather than the fact that the design is just really hard to read.
That the design is so difficult to read is done mainly to make the form pop out by contrast. It's a cool effect, but there's no way i'd deploy that for mass consumption. It's a piece of artwork in it's current state (albeit a really cool one).
Edit: Sorry, other people beat me to it. See other replies re:text colors.
However I agree about the contrast, I checked on my external dev monitor (vs. my super bright MBP screen) and the contrast could definitely use some work.
I'm "partial red-green" color blind. So, saturated, primary reds and greens I see as distinct. But if start to mix colores with some reds and greens, then I can see two colors as the same that other people see as distinct.
Partial red-green color blindness is very well understood. Nearly all colors that should be distinct still are but, yes, apparently I don't see fire engines and carrots just the same!
I'm such a man and mostly can't read that page.