I'm thinking this is a pipe dream. You can already run iOS within macOS in a simulator with Xcode, so not sure why Apple would bother implementing Dual Boot. Additionally, who wants to buy a device that gets dumbed down to iOS when you unhook it from a "dock"? You buy a Mac primarily for the capabilities it provides, particularly macOS. I don't even understand the benefit - you unhook the Mac from the dock, so what - you have to reboot into iOS or quit the Mac apps you have running to flip over to iOS in the case they figure out a way to make it "seamless" without rebooting, since your apps may to run under iOS? Seems like an annoyance which doesn't jive with Apple's MO is ease of use. If Apple ever goes to a touchscreen Mac, which they have said on record is not something they are not interested in doing - literally said by Steve Jobs, Tim Cook, Craig Federighi, Phil Schiller, etc., I will be very surprised.