Plawolf, I actually am applying Occam's razor here -- and that is why I posted the photo of the Chinese soldier with the strange "face mount" NVG configuration, to show that an NVG design involving a face mount does apparently exist in the PLA.
From there, the simplest answer is that the NVG mount we see in the picture we are discussing, is that the "cheek display" is really just a mount/stabilizer design which is a variant of the "face mount" in the picture I posted.
I can see why you think that, but it just doesn't fit.
Look closely at the pictures you have posted. Those "face brace" pictures you posted doesn't actually touch the face, its a scaffolding frame on which the NVGs are mounted, and the NVGs themselves swivel down, not up.
Its a very old design, which the PLA probably bought before they had helmets which come with NVG mounts attached.
That Norotos design you posted doesn't have cheek braces, rather cheek pads. Those are designed to make it more comfortable for the wearer as much as it is about providing a more secure and stable means to secure NVGs to someone's head.
That is a special forces/civilian market oriented product designed to be worn without a traditional NVG compatible ballistic helmet rather than with them.
In all cases, the brace doesn't secure by clamping onto the face, it secures by traditional chin straps. That picture from the exercise is not that clear, but we can see that whatever the soldiers are wearing, it doesn't extend all the way down to the chin.
The alternative idea of the cheek stabilizer being a "cheek display" like a mini HUD is frankly the far more unrealistic one, given how advanced such technology would be and that we likely would have seen some degree of such technology in recent years either via leaks or even possibly defense expos. The fact that they have shown recent "future soldier" concepts in recent years and have trialled it and leaked such configurations (including eyepieces integrated with rifles featuring cameras, or ZH-05) means we know what their most recent developments are, and so while it is possible that they could have developed an infantry based HUD without us getting a hint of it prior to actually deploying it in real exercises, it is also a very small possibility.
So how do leaks generally start? The PLA doesn't hold a press conference and put on a powerpoint presentation with handouts.
Official leaks typically start with short glimpses allowed in pictures and videos of PLA exercises and/or deployments.
All those examples you gave started off exactly like this - an almost carefully crafted teaser photo (notice how the soldier we can see wearing this is the only one with his helmet positioned oddly. The chin straps are taunt and well secured, so there is little reason his helmet should be push back so much to give us such a clear shot of the item in question) to show you enough to let you know they have something new and interesting, but not enough for you to make a positive determination of what it is.
I would expect more, better quality "leaks" of this to emerge in the months and years ahead.
Therefore, occam's razor tells me that it is far more likely that it's just a poor NVG mount design rather than an advanced high tech infantry HUD.
The craftsmanship evident in the details we can see is clear at odds with the suggestion that this a poorly designed outdated NVG mount.
The overall look and feel of it is very compact and modern looking, far more so then you would expect from a legacy system designed before helmet mounts became standard issue with top tier PLA units. In addition, the whole point of a cheek pad is to spread the pressure as wide as practical, so making it so compact doesn't make sense either. You want you cheek pads wide, not so narrow.
A wide pad also makes it far easier to cover a wide range of cheekbone shapes and sizes. That just doesn't mesh with the design shown.
It is also self-contradictory to insist that the PLA bought a face strap because it doesn't care about ergonomics when the whole point of a design with padded cheek pads would be to improve ergonomics and comfort for the wearer. Just like how its more comfortable to have wide, padded straps on your rucksack.
Moreover, if it is just some variation of a padded head strap for NVGs, we should have seen it already at defence expos and/or on the civilian market.
The only reason you don't actively advertise something is if it wasn't for sale.
Mini infantryman HUDs are advanced, but hardly revolutionary or beyond the technological reach of China.
The PLA is more current with technology then people give them credit for. ZH05, exo-suits, future soldier, just a few examples off the top of my head.
True enough they do not deploy much advanced tech large scale, but they are often more up to date with cutting-edge R&D than people think/expect, partly because they are saving money by not fielding fancy new kit large scale like other armies.
However, the PLA still wants to and needs to field test and evaluate new stuff their techs have developed.
Just because a picture of something showed up in carefully vetted and often actively staged PR shots from an exercise is no indication that that particular piece of kit is standard issue.