Exactly, any minor slight arguments in favor of the FX3 being their main/only camera is totally irrelevant once you look into how they were actually using the FX3! (for instance, always with an Atomos recorder and two timecode boxes on it, etc etc etc)
In my opinion, they should have used half a dozen or so FX6 bodies with maybe a couple or so FX3 bodies for the very niche uses of crash cam / drone camera. (although it appears they used GoPros as well??? Again, I'd lean towards choosing a Sony RX0 mk2 instead... you can get s-log with 4K 10bit 422 files out of it, with a S16 sized sensor)
Or $8M to spend on the production itself during filming.
Interesting, the Cam Op isn't even using the Atomos as a monitor! But has added a SmallHD as his monitor for operating with.