This seems like a less likely incentive than the expectation created by phones and tablets that the device become ready "instantly".

Qualcomm has moved into the laptop space and brands their products as "always-on, always-connected" such that your programs are not halted while the screen is inactive/lid is closed. Microsoft may feel like some of their laptops compete with iOS/Android devices that respond quicker. Maybe they want x86_64 Windows to work just as well as ARM Windows in this regard.