Except that was in reference to the demo they gave at GDC while using the editor. Not necessarily the card used to render the demo, someone should ask.

Update from one of the demo authors:

"The Adam demo runs in 1440p at 30fps on a GTX 980, by the way :) See it running real-time at the Unity booth at GDC!"

https://twitter.com/robertcupisz/status/710160351568986112

So it's very likely that the YouTube video was rendered with far better hardware.

And one Titan X gives 6.6 TFLOPS, single precision (peak)

From the youtube comments that was also buddy pulling a guess out of his butt.

Was the commenter making it up.

Nope, that's exactly what it led me to believe, but it is definitely not that.

Oops. Looks like I was wrong... This is a youtube video of a pre-baked "realtime" render.

Still impressive though...