Widely accepted that filamentary ReRam (such as WBT) requires...

Widely accepted that filamentary ReRam (such as WBT) requires error correction which will impede speed, see http://cadlab.ece.ucsb.edu/sites/default/files/papers/ISLPED_16_0.pdf

Speed is the critical parameter for Storage Class Memory (SCM). 4ds is non-filamentary (has interface switching across whole surface rather than through a filament) and no need for speed crippling error correction (also see 4ds website and their announcements).

All the existing filamentary ReRam players (and there are plenty) had aspirations for SCM, but have ended up playing in the embedded (rather than stand-alone) memory space - due to speed/density issues.