Hmmm... so, the average IOPS of 90000 is expected from a consumer grade SSD today. In a subsystem with compression and dedup running on a common file server with a semi-intelligent file system, on two-way mirrored data, the raw read performance of the disk should be about 180000. Considering dedup and compression, it should be 5-10 times that. Three-way and four-way mirror of hot data should increase performance greatly. With 10 way mirroring, 900000 should be realistic. Add RAM caching for reads and even more should be possible.
In 4U, there should never be a circumstance on an all-RAID platform which IOPS should ever be anywhere near as low as 320000. Did you miss a zero in the article or did they make a product designed for SCSI/NVMe over fabric protocols?