This is definitely a niche concept and not the "norm" or usual arrangement. Wide range adoption of the "vanishing stereo rack" will be unusual and or futuristic.
I love dedicated gear as much as anyone, and I am literally negotiating with my wife right now where the dedicated rack will go in our remodel. But make no mistake everyone, WE are the niche (and in many ways dying) concept, not lifestyle products. I would estimate that a single-digit percentage of my friends have a dedicated stereo at this point. Fractions of a percent if you count millennials and younger (I work with a lot of them).