As others have said, its a publicity stunt. But it's also a very strong message that G-Sync is going to remain proprietary. Nothing screams that like "hey we're putting this monitor tech you want us to share into new TVs".
Then they just need to seal the deal with next gen consoles and we are all doomed to suckle on nvidia's teet for ever more. I'm sure I saw an easy access flap under Jensons chest pocket.
It is sort of going against the point of PC gaming, which is to have high resolution, when you have 4k on 65" it is actually low resolution similar to a 32" 1080p screen.
But I don't think they can do that, to be honest when 120hz 4k HDMI 2.1 120hz adaptive sync is normal, lets say 2-5 years from now, Nvidia would really have to support it, or they would lose a lot of sales, people are not going to buy a Gsync 65" TV, when they could get a normal adaptive sync 120hz 4k OLED or something for less, I have almost zero interest in AMD GPU's anymore, because NVidia are consistantly making much better cards, I used to be interested in AMD back when it was about 290 etc.
BUT if for example I had a 120hz 4k HDMI 2.1 TV and the only way I could use that was AMD, then I would probably get AMD. As it is now I have Gsync monitor and 60hz TV so Nvidia is ok.