Modern NAS such as Synology or Terramaster or QNAP already work pretty well with Apple Products, and at a Price Apple won’tbe interested in playing at.
For Home Use which what would be looking at then no need for NVME performance hence why the NAS Vendors still HDD based with SSD Cache.
And when say Home Use then mean Home, not Home Based Workers.
A 6 Bay NAS running cut down MacOS that could function as an AppleTV Server without requiring a Mac would be nice.
Could be a low speed Mx 8Gb, 256Gb SSD to act as Cache.
Unique Selling Point would be be AppleTV Server App, however could almost gaurantee that there would be complaints from people about
A - the price, could see not see Apple selling for less than entry Mac Mini pricing.
B - lack of available of AppleTV Server App on other NAS, and then attempted to be forced to lauch AppleTV Server App for other NAS Platforms in the same way Time Capsule is available across other NAS.
At which point sales of Apple NAS like the Airport and TimeCapsule drops off. As such why bother with the spending on development from Apples perspective. If people really want an Apple NAS then Mini and External Storage Enclosure would be about nearest going to get.
Entry M1 min with 8/256 and should have a few years left support then continue with newer Mx Entry Mini as required.