I have a Dremel, and many other tools, sharp and not so much, that I'd be willing to apply to a case to fit one of these. It would
not be the first time I've... "abused" a personal case to fit hardware. Obviously review cases are reviewed as delivered
.
Only downside to this I can see is that all power supply and most fan cables (and any other cables) are sized for having to be run through the motherboard tray and be plugged in to all those awkward upward-facing connectors.
That leaves a lot of slack on the backside of the motherboard - you can certainly go to town bundling them all up, but in addition to motherboard manufacturers potentially following Gigabyte's idea / lead here, you then of course have cases that need revisions, and you'll probably want to look at power supplies with appropriately shortened cables. And then the GPU with the power on the bottom - which assumes that the GPU is longer than the motherboard, and is installed directly into a PCIe slot, i.e. without a riser cable or riser board.
It's a lot of variables covering a lot of industries to cover, and you'd pretty much need all of it to happen at once to take advantage of the benefits.