People requesting a touchscreen mac always gets the problem wrong. People do not feel the need to reach out and touch the screen, people hardly have the strength to reach for the touch bar. This is why leap motion failed, this is why the surface is a failure and why minority report interfaces will never be successful and why everyone hates the touch bar.
What IS interesting is to have a dockable iPad into a laptop just to reduce the number of devices you need to carry. So you have your MacBook set up at your work desk and you have to run for a meeting you just pick up the screen from the base and go, hand-off is seamless and the os switches to "portable/iPadOS" mode. Once you dock it you are back into macOS. Now that would make sense, but if you cannot get people to use the touch bar how on earth would you make them use the whole screen?
What IS interesting is to have a dockable iPad into a laptop just to reduce the number of devices you need to carry. So you have your MacBook set up at your work desk and you have to run for a meeting you just pick up the screen from the base and go, hand-off is seamless and the os switches to "portable/iPadOS" mode. Once you dock it you are back into macOS. Now that would make sense, but if you cannot get people to use the touch bar how on earth would you make them use the whole screen?