Misses the point
"few in the industry realized just how radical Optane was. And so it bombed"
No. The reality is: nobody wanted to buy it, and hence it bombed.
IMO, the fundamental premise of the article is mistaken. Optane was never suitable for primary storage, for the simple reason that even DRAM is already a massive system bottleneck. Whilst CPUs have increased in speed by 3-4 orders of magnitude over the last few decades, DRAM has increased by maybe 1 order of magnitude. As a result, any access to DRAM can result in hundreds of cycles of CPU stall. In current systems there need to be three levels of cache between the CPU and the DRAM for it to function tolerably at all.
Replacing your DRAM with Optane, making it another order of magnitude slower again, would make this far worse.
The only way it *might* have worked is to use Optane as further tier of caching between CPU and DRAM. But that requires reworking your applications and operating systems, copying data back and forth between Optane and DRAM as it gets hotter or colder - for at best marginal benefits.
That copying is pretty much like swapping. Optane would have been a good location for your swap file. But if you're having to swap out of DRAM, your performance is already suffering badly, and Optane would just make it suffer slightly less. Similarly, Optane could have been used for the page buffer to cache data fetched from SSD - but if your data is a small percentage hot and the rest cold, then the hot is already cached in DRAM anyway.
In short, it was an expensive solution looking for a problem. If it could have been made as cheap as SSD, then it would have won because of its higher speed and endurance. If it could have been made as fast as DRAM, then it would have won through lower cost-per-bit (and maybe some use could have been found for the persistence too). Neither of these was true. It was just another type of secondary storage but considerably more expensive than SSD, which the market considers "good enough" in that role.