Found this somehow and it's intriguing when comparing to M2 drives. It's not blistering fast w/ 3GB/s writes but, reads are double that.
In our Solidigm D5-P5430 review, we see how this 15.36TB PCIe Gen4 NVMe SSD performs and how it is optimized for hard drive displacement
For ~$1K though it blows an M2 out of the water for capacity being 2x8TB.
Of course being U2 you most likely need a U2 adapter but, those are fairly cheap.
$21 - https://www.amazon.com/GLOTRENDS-SFF-8639-Adapter-Desktop-Installation/dp/B099185SSV
$41 - https://www.amazon.com/Ableconn-PEXU2-132-2-5-inch-SFF-8639-Carrier/dp/B01D2PXUAQ
$14 - https://www.amazon.com/PCI-SFF-8639-Adapter-Intel-Motherboard/dp/B01LZEYFD1
$15 - https://www.amazon.com/NFHK-SFF-8639-Adapter-Extension-Express/dp/B096KHM7V1
$46 - https://www.amazon.com/Yunseity-HighPerformance-Converter-19-69inch-Adapter/dp/B0CDFWT3CK - converts an M2 to the 8639 on the SSD
$46 - https://www.amazon.com/Diyeeni-SFF-8639-Adapter-Converter-Compatible/dp/B07V579XN9 - same as prior
$24 - https://www.amazon.com/SFF-8643-SFF-8639-Server-Adapter-Cable/dp/B0C9CKHNXD - same as prior
$28 - https://www.amazon.com/DiLinKer-SFF-8639-Cable-PCIe-Adapter-U-2-Converter/dp/B07VB6L8SJ - same as prior