JFK ATC is definitely the unfriendliest and most arrogant ATC in the world, but I disagree that they are the worst. Apart from their non-standard phraseology, they are doing a good job in dealing with a lot of traffic in a congested airspace in my opinion.
They aren't as good as UK or German ATC, but they are absolutely not the worst.
Anyway, this incident isn't due to ATC, but it's another messed up approach by EK pilots. Unfortunately the reasons why these incident keep happening aren't being dealt with. The easiest is to blame the pilots and that is what EK management will do again.
More checking, more punishment, more complicated procedures and policies and even more restrictions in manual flying is what I fear will be the result.