@Leynos 

Not true.  I was told by reliable sources in the Sony camp that it was due to the Series S.

1080 60 is fine with me. Always prefer 1080 6FPS over 4k 30FPS

Its not about being more demanding, its more about the approach to development and how the games are made.  Graphics wise can be totally different at how they render the final image between games from different genres and when people who have no clue about the development process make analogies along those lines it just feels presumptuous.  While graphics are more a personal opinion as to how good something looks over the other, its always better to do comparisons to games that are structured more on the same lines like say Stalker and Avowed where both are open world games that may have a more similar make up and design decisions compared to a racer and a open world RPG.  Even still both games goes for a totally different look and feel and from what I have heard from a lot of people who had a chance to play the demo, it seems that the game does look really good so maybe the videos are not doing it all the justice it deserve.

As to Obsidian graphical ability I totally agree that this has never been a strong point of the studio but then again people who like their games probably isn't looking to see that level of graphical might from them anyway.