He didn't move the goalposts and usefully expanded on my point. Those devices you're talking about notably adhere to other external standards and are not typically user reprogrammable (where user is the integrator). Also important is that I would not consider them secure in general due to the standards they implement. You also certainly realize that their power consumption, when present, massively dwarfs the type of processor we were first discussing?
By the time you get to the ARMv8 accelerators, yes, you're going to exactly the same place I was arguing we should go with my original comment. There's actually a number of primitives that could be reused for various systems.
The original claim was that these parts were rare because of ITAR. They aren't rare, and ITAR doesn't have much to do with where they're present or absent. Shifting the argument to a different point about a specific accelerator or specific class of parts is exactly as I said: moving the goalposts.
The question of whether they're user programmable or not is nearer to the mark because EAR cares about it, but it still doesn't present a formidable barrier-- at least, I've been shipping parts with crypto accelerators at various levels of user configurability for a long time, and so has everybody else.
By the time you get to the ARMv8 accelerators, yes, you're going to exactly the same place I was arguing we should go with my original comment. There's actually a number of primitives that could be reused for various systems.