This is a great point! It is not NY in GENERAL, but rather the culture that has been created by two coaching staff's in recent years: Saratoga and FM. Having these cultures (within 2 hours of each other and in the same state of competition) is the reason that other NY teams and coaches are lifting up. Out of survival. The same thing likely occurs in CA. The difference is that the bar isn't quite as high in CA, and that is because CA is soft (especially when it comes to tough ass XC running).
The culture within the same PROGRAM (girls and boys combined) feeds off of each other. FM boys have been to the champs what, 5 years of 7? Not sure of that math. They have placed 2nd, 2nd, 3rd, 9th, 16th? I'd say that is definitive proof that it is in fact the coaching.
So, I suppose it isn't fair to say that it is all of NY, but rather two or three teams and coaches who are raising the bar in our Rift Valley of HS XC.