There goes the hopes of those expecting M5 to finally sort out the fate of Intel Mac Pro.
From my point of view they have to accept if they want a desktop like experience, only PCs with Windows/Linux/BSD are left standing as composable workstations.
No they aren't, because you forgot the little detail not every kind of PCIe card is supported, like those that folks using graphical workstations for CAD/CAM rendering, or those in VFX, might think of using.
Also not all kinds of high-speed network, or real time audio cards are supported.
Stuffing a Studio into a desktop case full of air, and limited set of supported PCIe cards, is a slap into the face of the hardcore users that still hope Apple cares about workstations.
From my point of view they have to accept if they want a desktop like experience, only PCs with Windows/Linux/BSD are left standing as composable workstations.