It was bound to happen. Wii slows to halt by year 5.

How do we explain that the PS4 for this quarter has shiped more than the Switch, when we could actually see the really far opposite result with at least Japan and NPD reports.
Even if VGC has overtracked the Switch in EU and RoW, it is not very logical.
The theory currently among some investors, is that Nintendo tried to reduce the stocks of the current model everywhere, with the goal in mind to replace a part of the transit stock with the new model coming soon.

Even if VGC adjusts the Switch lower...There is something weird here by reducing the transit stock that much, when the console was actually selling 26% faster than last year same quarter.

Yeah, I think it's likely that Nintendo is trying to reduce the number of units in transit to make way for a new model. It's definitely not overtracking: In their investor presentation, they acknowledged that sell-through in the March quarter was 35% up YoY in Japan/North America/Europe.

https://www.nintendo.co.jp/ir/pdf/2019/190426_3e.pdf

So even more weird...VGC tracked +26-27% for sales to consumers from 2018Q4 and 2019Q4, and Nintendo tracked* even much more.

*No offense to VGC, Nintendo's tracking methods might be even more accurate.

If I just apply a coef x1,35 on the last adjusted VGC 2018Q4 sales, I get this :

The lack of support from Nintendo as they shifted to Wii U prematurely killed it.

I think it would have been better if Nintendo continued supporting Wii, and perhaps released a Wii HD model in the interim, prior to the Switch. While some might call Wii U a Wii HD, it wasn't at all; it was a much slower console due to the really poor OS they gave it, and it required a "Wii Mode" in order to play Wii games, also the really expensive Gamepad controller.

If there is one place Sony consistently beats Nintendo at, it's generation transition.

It truly is amazing but one has to assume that to sell another 16 million this FY that a price drop has to happen. When will that come? Beating on 100 million at 299/399 is an accomplishment within itself. But 16 million is not that much lower than last FY so does that mean that they are holding off on lowering the price till late FY?

Switch is selling good but for the PS4 to be this old and still matching sales is beyond.

That's not what killed Wii. Wii was in decline in 2010 and into 2011. Wii's appeal only stretched so far, and its technology was definitely getting long in the tooth.