Ann: Q2FY19 Activities Update and Appendix 4C, page-109

It gets back to my earlier post, filamentary ReRam can't get the DRAM like speed (without error correction) required for SCM.

Hence, not surprising that wbt has explicitly changed focus to join all the other "early mover" filamentary ReRam companies who, despite aspirations of conquering the world, ended up producing embedded memory.

Based on current mkt cap, the market would appear to share your skepticism regarding 4ds achieving storage class memory.  However, Western Digital and imec clearly see something, and the industry is keenly waiting/watching for the data/results.   I suppose we will know soon enough.