That's for my "yes" part.
My "no" part is that is not a huge step down from the PS4", it's a global launch all around the world and the console was sold out within 2 hours worldwide, they sold everything they could potentially produce and sell. So yeah, Japan should've have more units perhaps, but that doesn't say much about the actual trends.
Well, I'd say that depends also on the worldwide sales figures.
If those can't keep up with the PS4 sales figures, then it's most certainly a big step down. If the PS5 however outsells the PS4 week over week by a fair margin, then the argument can be made that it's not a step down.
The Nintendo eShop rating Thread: http://gamrconnect.vgchartz.com/thread.php?id=237454
The Steam/GOG key gifting thread: https://gamrconnect.vgchartz.com/thread/242024/the-steamgog-key-gifting-thread/1/