I know this is a large thread so it's hard to keep up, but just to reiterate some things:
1) It's highly unlikely anyone will ever be able to port a linux video card driver to OSX. You may have seen drivers for other things (network cards etc) that people 'ported' to OSX, but those are much simpler things than video card drivers. The kernel architectures are completely different, not to mention you have to deal with the whole 'how do I make a metal driver' thing; which you aren't going to get any guidance for from a linux driver. I mean it's possible some rock star will come along and pull it off, but that's a long long shot.
2) The frontline support people don't know anything about this stuff. You're lucky if they even know there's an OSX driver to begin with. Do not believe anything they say about releases or the lack of them. In the same quoted passage above that claimed there is never going to be a 1080 driver, they immediately said something incorrect about the current one. To call the existing web drivers 'simple' and the bare minimum for the OS to recognize the card is pretty out there. I mean, it has G-SYNC support (added when Sierra released, I believe); that's going a bit beyond 'bare minimum'.
The only way anyone is going to know the fate of Pascal drivers is if they somehow manage to get someone in mid to upper nvidia management to make a statement. Companies tend to be pretty tight lipped about this stuff, though.