Why would they sell a device with 256GB of RAM as the lowest-spec device rather than making 8 32GB or 16 16GB machines as their entry-level?
Apple’s not exactly famous for their low pricing on spec upgrades nor competing based on being the price leader…
If 256GB of RAM enables them to run on-device AI models that (for reasons) are a key feature differentiator?
Personally, I think there's no way memory heavy inference moves on-device (vs cloud) due to the economics, but it's not impossible technology + platforms go that way for currently unforeseeable reasons.