It doesn't really have anything to do with the headset.the second video explicitly showed that.
The GPU on the Quest is likely 1/6th as capable of the PS4. Desktop GPUs took a bit to be reasonable. Mobile GPUs are a long ways behind (even the 7 year old PS4).
The saving graces are:
-The Quest 2 would likely have support to wirelessly connect to a PC
-something like DLSS would greatly bridge the gap
I would guess 4 years from now, a Quest standalone would be able to compete.