I'm assuming the endurance aspect is the thing that stops this...

I'm assuming the endurance aspect is the thing that stops this from being an outright replacement for DRAM. I've been wondering, given the supposed cost, energy, speed, and retention benefits why we are an augment and not just an outright replacement, and this makes sense to me. Yes our retention means that we don't need as much endurance, but only if it's writing and reading the same piece of information, which is dependent on the application.

Ultimately it will depend on the design but standard thinking (for DRAM at least) is that a smaller cell has more sensitivity to noise and other factors that can result in bit errors but then mitigating factors in less leakage, which 4DS already has. Exciting to see what turns out.