That's not true at all. The PC was all their main development machines anyway. The PS5's SSD can pass data to the GPU faster than the GPU can render the pixels. I don't think you have anything to worry about there.
Absolutely not.
Even the fastest SSDs have a latency of ~0.010 miliseconds.
L1 cache on RDNA2 has a latency of 27 nano seconds. L2 cache of 93ns.
Even the memory of the PS5 has a latency of 140ns.
This is several orders of magnitude faster than any SSD. No way an SSD can submit data in time to render pixels.
And then remember that the registers inside shader itself, is even faster than an L1 cache.
No f****** way an SSD can fill a register in time to render a pixel. Especially if that pixel has multiple passes.
Then there is the issue of memory bandwidth. The PS5 SSD has only 5.5 GB/s. Even considering best case scenario with data being fully compressed, maybe 25Gb/s
The vram of The PS5 has 448GB/s. This is 18 times more than the SSD at it's best case scenario.
How could an SSD expect to fill all those CUs with this tiny amount of memory bandwidth....