I saw this and thought it could be interesting to someone building a tower-based server. “spoiler” looks like up to 8 3.5" sata drives(with optional purchase, 4 without) with 3 2.5" sata drives on the back of the motherboard. 11 pci/pcie brackets on the back of the case. and 4 gpu support brackets.
The crazy thing is that Silverstone also showed off a case for this motherboard form factor at this year’s Computex, but Supermicro killed off the 15.12" x 13.2" form factor likely because it’s no longer viable with PCIe 5.0; the last board they released in this form factor was a PCI 4.0 board.
For not much more then this case costs you can get a 24 bay rack mountable enclosure from China:
(no affiliation!)
Bonus: it has hot-swap drive bays! Admittedly, fitting 4 full size GPU’s is a bit of a challenge, but if you can shell out for that many video cards, the considerable price of the case doesn’t worry you anyway 
I’ve seen the review from Jay, Enthoo is aiming for a niche market and you can expect pricing accordingly.