The Allies almost always have the high ground and the N1K2 can no longer do the rapid 180 and spray and pray at 800 yards to get kills.
AH2 is a whole new game in regards to the N1K2 vs F4U. Speed means a lot more than it did in AH1.
Don't get me wrong, the N1K2 will kill a lot more F4U's than the Ki-61 or A6M5 did, but the F4U will kill a lot of N1K2s as well.