Please refer to this user guide, dated November 2019, which discusses Intel VROC on Linux systems specifically. Section 3.1 lists the Linux distributions that support Intel VROC (namely, RHEL and SLES). I can confirm that Intel VROC works on Rhel 7.6.
Please refer to this FAQ which discusses Intel VROC technology generally. In particular, this technology is a special consequence of Intel’s CPU architecture (namely, the ability to connect NVMe drives directly to Xeon PCie lanes). To the best of my knowledge, Intel VROC is the most performant RAID solution when dealing with large arrays of NVMe drives.
It is perplexing that Clear Linux, being Intel’s operating system, does not support Intel VROC, being Intel’s high performance RAID solution. This seems to be exactly the type of feature that Clear Linux should support, given the operating system’s goal to extract maximum capabilities from Intel CPUs.