Optane was a very interesting technology but I don't think it as revolutionary as the article makes it to be. First, Optane does not make the memory hierarchy simpler as you still need fast RAM to solve the write endurance problem. Second, it is not obvious that Optane would be cost-competitive with SSDs. Third, you don't need a tech like that to implement a persistent memory system like one described in the article: just use RAM backed by an SSD and a battery/capacitor to flush the dirty pages in an event of power failure. I think Apple does something like this in their newer devices.

This indeed leaves Optane as a limited-use enterprise persistent cache technology.