I also believe that a strong reason that Optane pdimm's failed, was that it was only available on enterprise servers so hackers didn't get a chance to play with it and build software that took advantage of this special hardware.
Just look at how specialized Infiniband is, even though its awesome and has some great use cases. If it was a commodity tech, there would be 100x times more applications/software that took advantage of it.
this is approximately the same discussion as with ECC RAM: the benefits vastly outweigh the slight performance loss and die area increases.
Memory encryption, on the other hand, provides absolutely no benefit to 99.999% of users. If you consider yourself to be such a high value target that you suspect someone might gain physical access to your hardware without your knowledge and carry out extremely sophisticated hardware attacks to extract your data, you are a tiny minority and it makes sense that such niche protections would require buying specialized hardware. Even then, the odds of such an attack being chosen instead of a far less sophisticated software-based approach are also tiny.
Of course, if the hardware itself supports the feature and AMD simply decided to disable it, that's still a shitty thing to do, but let's not pretend that it is in any way comparable to ECC.
No benefit for 99%? people said the same about FDE. Just as there is not a good enough excuse to not validate integrity and availability of data, it is not for confidentiality when its very much technically possible to do so.
There are many people, myself included who opt to use security features like this. All this does is reduce security for folks without any legitimate reason. “Power consumption” is absolutely not a valid excuse to completely disable it.
I’ve been a fan of AMD for a while now but they’re really jumping the shark these days. It’s a real shit situation we’re all in because of the lack of competition in consumer CPUs. I can only hope things like RISCV take off sooner than later.