They can absolutely make the iPad Pro run macOS just fine and figure out the software solution quite easily.
They just need to make it run macOS by default but with an UI layer that could transform it in an iOS like UI in a pinch (while shutting down most of the daemons and stuff iPad OS doesn't use currently). You can already run iPad apps on Apple Silicon macs just fine.
It's purely and simply a commercial decision, to force people to buy multiple devices. If the iPad could run as a Mac they would lose a large amount of MacBook Air and low-end MacBook Pros, this is a simple as that.
They can absolutely make the iPad Pro run macOS just fine and figure out the software solution quite easily.
They just need to make it run macOS by default but with an UI layer that could transform it in an iOS like UI in a pinch (while shutting down most of the daemons and stuff iPad OS doesn't use currently). You can already run iPad apps on Apple Silicon macs just fine.
It's purely and simply a commercial decision, to force people to buy multiple devices. If the iPad could run as a Mac they would lose a large amount of MacBook Air and low-end MacBook Pros, this is a simple as that.