A false dichotomy if ever there was one. Anyone who doesn't think the code is ugly must just be blinded by hero worship?
How about the possibility that a1a is one of the people who just automatically equates "large volume of code" with "spaghetti"? In my experience there is a fair number of HN users (and devs in general) with this knee-jerk perspective.
In my very humble opinion any reasonable person who takes a few minutes to actually read through this code would never call it spaghetti. _Especially_ considering 1) the feature set of PHP at the time the code was leaked, 2) the immense scale of Facebook even at that time.