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So much of this is hearsay left over from a long time ago.
When carburetors ruled the planet, the old "Italian Tuneup" did have merit. Running the engine up the power-band did produce benefits in cleaner valves, chambers and oiling. However, modern closed loop systems run cleaner in partial load ranges. Much cleaner in fact than the open looped full throttle rich setting. This is independent of engine revolutions. As someone pointed out, simply running the car at a constant and warmed operating cycle will benefit a commuter vehicle. Running the engine up to red-line does nothing at all. This is assuming the engine is running properly.
The photo of the in cylinder carbon above the ring band is true for pretty much all vehicles to varying degrees. The quenching effect of the piston wall and cylinder wall keep fuel that is trapped in this space from reaching combustion temperature.
The mention of gasoline direct injected engines fouling is a product of exhaust gas recirculation (EGR) systems and positive crank case (PCV) ventilation recirculation. The residue builds up on the back of the intake valve with no liquid gasoline to wash it off. High revs do little to help this situation.
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