He's guessing, from a maintenance point of view. Though as if the J-36 really cares about maintenance ease. There's three engines, at least two of which will be adaptive cycle engines. It's not like the J-36 are projected to be procured on a massive scale (based on projected costs) anyways. The maintenance folks will just have to deal with it nonetheless. They'll live.
No there was a comment (that might be deleted now) where he directly implies Ayi is wrong and is just speculating