It would make sense for Apple to fork their next highest-end Mac Studio motherboard, make relatively minor changes to it (e.g. add a higher bandwidth NIC and strip out unnecessary I/O) then wrap multiples of those into a rack mount chassis, with commodity-grade cooling and power supply solutions appropriate for the context.
Combined with a properly headless fork of their OS stack (think Darwin, not OS X Server) they could spin up a highly competitive solution using entirely "B-team" resources.
...then it would be piped through their design-council, run through 5 more iterations to get a unique unibody case for it, accompanied by an optional proprietary Apple rack and a price-tag triple of the competition.
That's along the lines of how it usually rolls whenever Apple tries to make something purely utilitarian, it's the most considerate and "fresh" look at a product, but ultimately designed to be used and then disposed when finished.
A purely utilitarian IT-appliance without a individual end-user doesn't seem to be possible in their product pipeline, you usually end up with something "Prosumer": Impressive on its own, yet of degraded maintainability and scalability.
It's like asking Bugatti to design a public transport bus. It would surely be an impressive bus, but not one you would want to maintain over years at a scale of hundreds.
