Isn't basically the same vision Canonical had for Ubuntu Touch/Phone?
You carry your (main) computer with you in your pocket. If you're on the go, you use its screen. If at home, you plug it in better screens/inputs peripherals.
I wish they had had the firepower to develop this. I'm not exactly unhappy with Android, but I'd bought that in an instant.
Many have had this concept, no one has actually executed well on it.
My use case is pretty fine, I think. I use vscode's ssh development feature to remote into my desktop at home. My laptop just needs to run a browser and editor window which I think an M1 powered iphone would be fine at.