In fact, no, if you watch their video, they specifically state that they don't know if the footage was caught on PC or Xbox (@13:55).
Scaling back graphical features to achieve the higher target 60fps is exactly what all "Performance Modes" on consoles are. There is nothing reported indicating the primary 4K@30fps mode nerfs anything at all besides limiting to the 30fps target itself.
"It looks absolutely phenomenal. The sheer density that they're going for here, in terms of materials, in terms of environmental details, when they're talking about going down to a single needle in a cactus (laughs incredulously)...that's just phenomenal, really. I mentioned initial disappointment that it was talking about in-engine footage, where you didn't really know what you were looking at, interestingly labeled as in-game footage on the Youtube trailer...the actual gameplay we saw that was clearly, you know, the actual code running, has that same level of detail, and they actually had these specific shots where when they move over to a new player, it lingers on the detail, you get this sort of like beautiful vista shot, and then the player kind of swoops in, it was a beautiful way to demonstrate that this is REAL, this is the game, you know, I can't really say anything more than that, it just looks amazing (laughing in disbelief)."
- John Linneman