Has anyone considered that that a 27in isn't currently possible based on thermal limitations of the new form factor?
Apple used to sell an iMac with virtually the same display, built in power supply and an Intel i9 space heater, plus discrete GPU. They used to sell another version with a better cooler and an 18 core Xeon.... Half the point of Apple Silicon is that it produces more performance for less heat c.f. Intel. If they can put an M1 Max in a 14" MacBook Pro, putting one in a 27" all-in-one should not break the laws of physics.
The only way the "thermal limitations of the new form factor" should be a problem is if some genius designed the "new form factor" on purely cosmetic grounds without considering the thermal requirements of the processors they needed to fit in it. Which would be stupid.
This seems like streamlining the product line - rather than producing a "Mac Pro Mini" (Mac Studio)
and a 5k iMac replacement - which would compete for the same market - they've produced the Studio Display which they can sell to to Mac Studio buyers who want the next best thing to an iMac
and MacBook Pro users who want a docking station.
I think people are getting carried away by this whole "It has fans and an A13 because it was born to be an iMac" thing. Most likely it has fans because it (a) has extra bright, hot LEDs for the 600 nit display and (b) contains a whacking great power supply so it can run the screen, the LEDs
and deliver 100W to a MacBook Pro
and power a bunch of USB-C devices. The A13? Pretty common for mid/high-end displays and TVs to have fairly powerful processors for image scaling/interpolation, so why would Apple buy something from Samsung or Broadcom when they made the A13 themselves? Probably about the only candidate that can display the startup logo on a 5k panel...