Earlier quoted context omitted.
That portal transition effect likely hides the load screen - it's still there, nearly half a second, it's just shorter. This is comparable to current load times with an SSD on PC!
The difference with PCs is that since the hardware is standard, developers can now create gameplay that depends on those capabilities. Until all (or most) PCs are equiped with high performance NVMe SSDs, those kind of features won't be possible other than on consoles. Also, the PS5's architecture is optimized end-to-end for faster loading times, it's more than just faster storage.
No one is going to design gameplay for a special hardware constraint unless the gameplay can degrade to lowest common denominator. Which of course, makes needing the special hardware optional.
There are few exceptions to this rule. Some platforms pay for exclusivity, effectively covering lost revenue from other platform streams. And Nintendo alone makes a profit on hardware, so they can produce platform exclusives to drive addtl revenue from hardware sales.
Special SSD pipelines, while PC gamers are still using 7200rpm HDDs, are about as appetizing to game devs as waggle controls or Kinect sensor games.
The new consoles include these SSDs not to make something possible now, but to remain relevant in ten years time when PCs may have caught up.
This is the game industry's equivalent of supporting IE 11.