This could indicate a cause rooted in his mistrust of aircraft carriers in peer conflict.
The thing is, you drastically increase carrier survivability by placing them further away from the source of potential harm. Yet removing them further and further away from the hot zones diminishes how effective they will be able to contribute to the effort.
How do you solve this issue? By having a very capable, survivable, long range strike aircraft that can be launched from the carrier and be supported by carrier borne aerial refueling. F/A-XX and in a sense also MQ-25, together with E-2D are what help a carrier to remain effective as a means of delivering strikes while being as far away from any potential harm as possible.
That's why, if one heavily relies on carriers, investing into potent carrier capable fighters is not only mandatory, it also just complements the inherent aspects of the aircraft carrier.
And there is no substitute for that, it's that easy. Any usable airfield that's in range of Chinese missiles and drones will be turned completely unusable very quickly in a direct conflict, so land based fighters in the region are not truly viable. The most versatile and survivable option remains the CVN, armed with powerful strike fighters, launching airborne early warning and aerial refueling aircraft, supported by several vessels completely dedicated to anti-air and anti-missile operations targeting the carrier above all else and submarines lurking beneath.
It is ultimately much harder for an adversary to bring assets into play that can reliably engage a carrier strike group, which is maneuvering, actively interfering with offensive efforts against it and protected by a multilayered defense against air, surface and subsurface threats.
I do not think the aircraft carrier is invincible, I also wouldn't give them high survival rates when deployed against an adversary like the PLA. But the amount of missiles, drones, aircraft, ships and submarines it will take to "melt" through the escorts and their arsenal, the airwing and lastly the carrier may turn this exchange into something more favorable, if not at least equally hurtful for both sides. It's not necessarily about the USN hoping to curbstomp the PLAN, PLAAF and PLARF, nor the PLA curbstomping the USN and USAF long range aviation. It's more so about making your particular adversary bleed so much that the cost of continued conflict becomes untenable. This will most likely mean that your own forces will suffer heavy losses too, so it's about who "bleeds out" first relative to their willingness to commit to an all out total war.
And the F/A-XX is one of many individual pieces in a machine that is intended to hurt an opponent as much as possible, as effectively and safely as possible while minimizing the own risk. Risk to itself due to being designed according to envisioned next generation designs, but also reducing risk to it's host vessel by allowing it through it's own distinct capabilities to operate from safer areas. And because of this F/A-XX and super carriers are irreplaceable for the USN if they want to remain competitive. A restart, long pause or cancelation of the F/A-XX would ultimately make US forces more vulnerable and deny them of enhanced offensive capabilities. And if one thinks about the prospect of a Chinese naval next generation fighter, be it 'J-50' or something else, all of the advantages recounted above would fall into their side of the court. US carriers would be at higher risk, their airwings would be less effective and and escorts and their stockpiles could be depleted quicker before closing in further on relevant positions.