For at least for the next year to two years after the new consoles are released,it will be the older consoles determining the base specifications as they will have a much bigger userbase. The same goes with PCs,most PCs at best will have a SATA SSD,but not NVME,so this is why most games seem to be fine on a SATA device still.
If you suddenly expect games to need a PCI-E 4.0 SSD,it will crater sales on console,and also on PC as the cost is still prohibitive and there is minimal support on desktop. I know no one who has an X570 motherboard with an AM4 system,and no one who has a PCI-E 4.0 SSD - almost all PC gamers I know will have a SATA SSD of some sort. Then you have the other problem,that Intel systems don't use PCI-E 4.0 either,ie,all those higher Core i7 9700K and Core i9 9900K/9900KS PCs,which are limited to SATA and PCI-E 3.0 NVME SSDs.
Also,another thing people have missed is the raw throughput of the NVME SSDs used in the XBox is capped to 2400MB/S to prevent overheating and to have consistent performance. Yes,there is compression involved in this which increases effective bandwidth,but I would expect a reasonably solid PCI-E 3.0 NVME SSD to be fine for the immediate future.
I also play an example of a game which hammers storage,ie,modded Fallout 4 with 200+ mods. The games is unplayable on a normal HDD in this state,and needs an SSD. Looking at the SSD monitoring software I can see upto 800~900MB/S peaks sometimes.
Majority of m.2 drives run far faster (3.5gb/s) and they still give you nothing but marginally faster loading times over say 500mb/s SSD.
I’m sure devs will start to take advantage of it but still 1TB is reasonably low by today’s standards. I have 4TB SSD’s in my pc and even those are running low.
£150 for a storage increase seems a bit backwards console wise to me. 100gb AAA games these days are quite common so what does 1TB get you?
Would be a bit odd if the games are going to run like absolute tosh if hooked up to anything other than an nvme drive.