Because Microsoft is the one who needs to do it - or maybe Apple.
Both have an ecosystem that operates in both worlds (though Microsoft keeps killing their phones and doesn't currently have one) - so they could do it.
It's obvious that the iPad could be a Mac now, there's no technical limitation. So the iPhone could be, too.
This seems like such a killer feature to me. And every time I watch a video of someone trying out DeX it seems to work so well.
Yet it never seems to take off. I don't understand why. What am I missing? App ecosystem not good enough for business use?
"This is the year of mobile-docking-replacing-workstations" has kind of become my "This is the year of Linux on the desktop.