I did not say anything like that. You fail to understand the concept.
What I said, in effect, was that the car would accelerate harder if it did not have an extra bog/pause at each upshift because there was a large step down in thrust (wheel torque) in each higher gear.
The graph is somewhat misleading.
The gap in real wheel torque between gears is not nearly as large (could even be non-existent) as the graph makes it seem.
When you're quickly accelerating in a low gear a lot of the engine power goes to spinning the engine and drive train up to speed. This means that the wheel torque applied to the ground (especially in low gears) when accelerating is a lot lower than what the graph shows.