I don't agree with what you are saying. The end result can certainly be affected by the difference in RAM, to say it doesn't matter is self-contradictory. As that one dude who is spreading garbage said (one of the few things he has a real point on), GDDR5 has a memory bandwidth nearly triple that of the Xbox One's DDR3, so it can definitely have some effect on the outcome, though we can't really tell what the extent is when we don't know the restrictions of the console (is the issues with resolution 100% related to hardware, and if so, is the GPU the only strained part in the matter?).
Personally, I wouldn't cancel my pre-order, but I'd probably put it on eBay to make a little money, if possible. I'd definitely be in the act of reassessment the hardware landscape though, that's for sure. I wouldn't be debating Xbox or PlayStation, but I'd be questioning Xbox or PC with this news. As for the greatness of the Kinect, it and the system allegedly eat up something like 10% of the hardware (what I read didn't specify what "system" entails, and how that 10% is split). I wouldn't be surprised if the highly-detailed Kinect was chomping away at the GPU a bit for image processing, though.
If the Kinect is part of the problem, it's an interesting discussion to have long-term. If motion gaming becomes popular, and Sony has to push the Eye's features more, I can't help but wonder if they'd run into hardware restrictions as the Eye used up resources, assuming the idea that the Kinect uses a significant chunk of resources.