Close but no cigar, it's the apps I want not the OS. What really makes sense would be native containerization of MacOS. This would be more efficient than a full VM and allow still Mac apps to run alongside iPadOS apps on the iPad. Containerization adds just the missing parts of MacOS and does not require booting MacOS. Essential a mirror of how iPad apps run under MacOS now.
MacOS is the wrong operating system for the iPad, but containerization would allow Mac apps to run within iPadOS with the Magic Keyboard or other keyboard and mouse. Containerized MacOS apps would preserve the security advantages of iOS. Requiring a physical keyboard and pointer avoids the interface problems of trying to work apps designed for a keyboard and pointer through a touch interface. Enabling the virtualization interface on iOS could also open the door to containerized ARM Windows apps running on the iPad without requiring a full Windows VM boot. The same containerization could allow MacOS apps to run natively on the Vision Pro.
The long game may be apps that run equally well with Vision, touch, or keyboard interfaces but MacOS app containers would be very useful in making the most powerful apps run on all the Apple platforms in the long transition. I'd love to see this as a surprise at WWDC.