You're asking for density or cheaper prices, but neither happened. The endurance improved, the IOPS improved, even latency a bit, but density didn't. Or it would've been cheaper than it is. I want to relate this to other forms of storage that went by the wayside, but I hope someone else will try again with a different roadmap and make it work.
FGPAs or SOCs with Optane for instant on/low latency applications would've been amazing.