I don't understand why the PS5 got such a huge boost. The console is expensive af, over twice as expensive as the PS4 was at a similar point in time, and has a much stronger competition from PC which got Wilds at launch. I also thought all these news about the "massively popular" PS5 rental in Japan would translate to something.

It was on the PSP and PS4 also.

Because it won't be late. If it's within the launch Window, it will pass PS5 version in sales. And the PS5 can't survive on Monster Hunter alone. Switch 2 will drown the PS5 once it is fully unveiled and released in Japan. It's not even a battle with Switch 1.

Most of the people who'll buy Wilds in Japan will have already done so by then though so it wouldn't pass it especially since it'd be on a new platform with a low install base for a while. For the impact of the Switch 2 on the PS5 in Japan in general it's gonna be releasing too late in the PS5's life to have a major impact on its trajectory. Like the PS5 is gonna be at least 4.5 years old when the Switch 2 releases and will have already sold about 70% of what it's gonna sell lifetime by then.

Based off the PS5s performance profile I think it's safe to say a Switch 2 Port is unlikely to arrive until the holiday at earliest.

Overall I think PS5 is safe in that games far in development will be built around it's specs and typically still take 6months or so to get an optimised Switch 2 version ready. 

The System is 80% towards the recent lifetime expectation for Sony hardware (9m), so I don't see anything dramatic happening to its longterm success. PS6 however is another question.

Because Wilds is the only massive franchise game that in Japan will be console exclusive to PS5 (Given that Xbox is dead there). DQ12 will also come to Switch 2, and will boost Switch 2 more as an example. Most other franchises that are massive in Japan will be Switch 2 console exclusives, which will be terrible for PS5 selling potential, just like it was for PS4 in Japan when the Switch released.

Wilds must have high digital numbers as that's actually half of what World and Rise did at retail on launch.

Boost it more sure but it'll still impact the PS5 as well. The 3DS got a bigger boost from DQ11 but it still gave the PS4 a notable boost as well. With Wilds still giving the PS5 a big boost despite it being significantly more expensive than the PS4, it being on PC at launch and PC having grown a lot in Japan lately I think the PS5 will be just fine with big releases that are on the Switch 2 as well like DQ12. Now the general baseline will of course continue to not be good so I'm not saying that the PS5 is in a great position in Japan or anything like that, just that even though software has declined on Playstation things are not looking as bad for the brand in Japan as they were a couple years ago.

I heard somewhere that PS5 has upwards of 80% digital share.  I'm one of those people who made the transition to nearly all digital.  There are obviously drawbacks but the convience is just too high.  I also have a Pro and I installed an extra hard drive so I have tons of space.  Not needing to uninstall anything really makes it easier to just download everything.  I also own ALOT of games and it really was taking up too much space for me.    But yes these figures imply that the total week one sales are between 1.5 and 2 million. 

Also, I find it really odd that MH isn't charting on Xbox.  Even with the muted install base it should be be doing at least 20k.  Then again, the digital share on Xbox is probably even higher considering the X/S lifetime breakdown compared to the PS5.

After some more investigation I have some more notes. "Monster Hunter Wilds takes the top spot. Total sales worldwide exceed 8 million copies."
Okay right there that is a massive boon for Capcom make over half a billion in the first week. For the PS5 that is huge when considering Steam numbers. Next, the 11-30 spots have been posted by Famitsu and it turns out that MH didn't chart on the top 30 (with the threshold for entry being about only 1500) units. This just doesnt seem right. Is MH exclusive in Japan? The big console's may be skewed towards digital sales in Japan than we realize.

After even more investigation I find that the current Xbox break down in Japan is:
Xbox Series S – 640 (332,626)
Xbox Series X Digital Edition – 46 (19,889)
Xbox Series X – 35 (319,519)

This means that over 50% of all Xbox consoles DO NOT take physical media at all. Then if you add the digital share of sales on top of that you probably on only have an addressable count of like 170k units. Even then with MH having an physical attach rate of 10% on the PS5, you would expect Xbox MH physical sales to pass 10k. So clearly there is something I'm missing here. I'm guessing its just not being sold on Xbox at retail in Japan.