You didn't know K-On? Boy...

 The PS4 can barely do 1440p proper in most cases. It has a bandwidth limitation and it was not a 100% bespoke design, wheras Scorpio is custom built for the task at hand. It takes a first party who's engines are built around he hardware to extrapolate the most from it. 

Scorpio can't run everything at 4K, but it has the resources that if the proper attention to engine optimization is done it is feasible. Like any hardware there is a learning curve and first party are always the ones that exercise the best proof of concept in execution because their engines are built around the hardware.

The fact that 3rd party like Ubisoft is already running the latest AC in 4K off the bat is impressive, since AC games are notoriously resource hogs on PC. If you recall Sony had no such luck with PS4 Pro at launch with marquee 3rd party titles and resorted to checkeboarding off the bat.

Xbox one X will prove to be more consistent in delivering 4K games than the naysayers believe.

What about the pixels man? The pixels!

Imaging chewing a spoonful of sand.  That's how real.....

This was expected by some of us. No way it was guaranteed native 4K across all titles. The difference I think between Pro and XOneX should be the following:

Pro 1440p -> X 1800p
Pro 1800p -> X 2160p

Differences between both should be similar to current standard PS4 to Xone.

I was going to write that. It's exactly as I see it as well and what you should expect looking at the spec's. I think the pro will win easily though thanks to its lower cost design with more competitive pricing but you never know stranger things have happened I'm certainly not saying the X can't make some decent sales. I have a suspicion Microsoft will realise fairly soon they are going to have to drop to close or even parity with PS4 pro pricing to get high sales and then it will get more interesting. I'm in the UK which I think is the second biggest market for Xbox consoles after the US.