> For something like a cache on a CPU (the main use of SRAM), what's the purpose of it being non-volatile? SRAM doesn't need refreshing, and it's a relatively small percentage of total power.

It sounds like it would be chosen for other reasons, and there would no purpose for the non-volitiliy beyond it being a nice-to-have in some weird scenarios.

Sort of like using core as main memory. That was just the main memory technology of its day, it happened to be non-volatile, but that wasn't it's main selling point.