Nikon says this is not true: https://www.nikon.com/news/2022/0712_01.htm
Perhaps...but this statement sounds awfully weaselly to me, i.e. 'we don't currently have any plans for layoffs' pronouncements that corporations often make right before announcing layoffs.
Nikon has a pretty long history (in Western memory going back to the Nikon S) of executing well and consistently. They're often not the first mover: Nikon S was a "best of" Zeiss-Leica body (pretty much all Zeiss, but using the Leitz shutter - this is why Nikon lenses mount, focus and zoom to the left), became quite popular. Nikon F wasn't the first SLR system, either, but well executed and became the benchmark.
A mirrorless system does not create better pictures. It does increase the likelihood that you capture the image you want at all.
Sure there is. For example consider the problems involved in taking a high resolution picture for a fast moving but difficult to focus object in low light. A Z9 will do brilliantly but cheaper cameras -- not so much.
A camera is not just the image sensor, modern sensors are all fairly close technologically in the grand scheme of things.
The electronic shutter in a rolling shutter CMOS is very similar: The first curtain is where rows of pixels are reset, the second curtain is when they are sampled/read out and digitized. For normal camera sensors this takes between 1/20s and 1/60s, depending on the resolution - high resolution cameras take longer.
The limiting factor for that isn't actually the pixel array itself, but the speed at which data can be transferred off the sensor. This is where stacked sensors come in: you can move data way more quickly between the front sensor die and the back logic/storage die than you can move it off chip. So the trick of the fast stacked sensors is that they read the image from the sensor die into the memory die, and then transfer the image through the usual, much slower link to the image DSP. But at that point the image has been fully exposed and the slowness of the link doesn't matter, except for the maximum frames per second.
This way you can make an image ~50 MP sensor whose electronic "shutter curtains" travel at a similar speed as the shutter curtains of a mechanical fp-shutter and so you don't reeallly need the mechanical shutter any more, because the motion artifacts will be basically the same. There are some edge cases, e.g. high frequency flickering light sources can apparently create issues, but they don't seem to be a show-stopper.
(There are some additional tricks, like CMOS sensors have been column-parallel for a long time, where each column of pixels have their own PGA and ADC, but these newer sensors seem to sample multiple rows in parallel as well)
((There are also global-shutter CMOS sensors, which can "near simultaneously" sample all pixels in the array, in the analog domain, but since this requires extra transistors in each pixel, it's always detrimental to other parameters for a ceteris paribus rolling shutter sensor. These are used mostly for machine vision / slow motion purposes. Higher-spec global shutter sensors are export controlled.))
The only other camera from the big 3 flagships that matches this speed is the Sony A1 with 1/250s. The Canon R3 is 1/180s. It has a mechanical shutter, but I think the Z9 proves that its worth the omission in 99% of the shooting scenarios. Especially when it is coming in $1000 cheaper than the Sony.
Edit: I was beaten to it!
Notice how they didn't mention continuation of "DEVELOPMENT"!
Good news so for people buying used, like myself!
https://petapixel.com/2020/10/06/nikon-has-finally-discontin...
The OP says "Nikkei has learned", so presumably they have some source telling them this and how true it is depends on how reliable the source is.