The localizers are not SE's development/writing team as a whole. Everything they do still has to be given the approval of the core production team. Having localizers contribute as much as they have is not unusual for game development, and trying to overstate this fact as a way to argue that the game is not 'JP First' is just dishonest.
FFXIV is most certainly a Japanese product first and foremost. The reality is that non-Japanese players are exactly what you said they weren't, which is a bonus. The game would not exist in the state that it is in without the support of their native market, which is impossible to ignore from an end-user perspective.
I concede that he asked that Japanese players do a second play-through in English, but it's still a game designed with a Japanese audience in mind, but if by chance it lives up to the 'global audiences' intention, then hopefully SE will be able to pivot with whatever their next project is, otherwise they will risk losing much, much more than a few sales, which is probably why it did so poor in terms of both Japanese sales and worldwide sales.
I strongly identify with the Japanese complaints against not having proper lip sync support for what is objectively their target demographic and most accessible language option, but I guess that's Square's bed and they've gotta lay in it.
I hope they'll put forth the effort to do proper facial animations for their native demographic, or use this as an incentive to at least translate the spoken language into a textual form, that way what's being heard lines up more closely with what's being read.
This doesn't really mean anything, and I said that I would have expected them to screen Game of Thrones to familiarize themselves with the medieval, grim and dark themes and all that which is something that they wanted to capture for FFXVI. Ghosts of Tsushima was developed by an American game studio (Sucker Punch Prod.) and is set in ancient Japan, but the game is primarily designed for a Western audience with Sony (a Japanese company) acting as the global publisher.