I am not sure if you are American or have knowledge of famous Supreme Court hearings, but I'll throw this quote out there "I know it when I see it."
Despite having trappings that some RPGs do, it just comes off as something entirely different. It does having certain criteria you can present in a list that could question my decision. All in all, FFXVI might meet the mechanic criteria to technically be an RPG; however I know it when I see it, and what I see is not an RPG.
Good enough for the Supreme Court, good enough for me.
en.m.wikipedia.org