I think one of the major missing factors is lack of OS support for the sorts of features that NVDIMM could potentially bring to the table. Super-fast wake from

I think one of the major missing factors is lack of OS support for the sorts of features that NVDIMM could potentially bring to the table. Super-fast wake from deep hibernation is just a starting point, the real work is re-writing every line of code written since the dawn of computing which starts from the two assumptions "one kind of storage is persistent and slow" and "the other kind of storage is volatile and fast". HPE made noise about challenging those assumptions with The Machine but predictably lost interest as their own memristor technology lost steam.