In this case, the new Soft Engine has been spoken about a lot. Of course they would make a comparison video to show the new engine off, which would be most noticeable in the bust. I don't see the big deal.
Btw the PS3 and PS4 comparison is used only for comparing the different textures and lightingn. The "Natural" mode in the right will be included in DoA5LR too, on the left is used the more "LR" (called "Soft" in Japan) mode exclusive of the current generation.
Make sense that they compared the Last Round mode to Natural because both of them are made with the purpose to make appear realistic the bounce (contrarily to "DoA" or "OMG").
Just a sidenote for explaining better the video... nothing of important, don't worry XD