Does french press plunger speed affect the taste? If you slowly press the plunger of a french press down will you get a stronger flavor in contrast to plunging rapidly? Does the speed of plunging affect anything?
Speed of the plunger does not affect the flavor.

When coffee is brewed in a french press, the main parameters are (apart from the coffee itself)


the temperature of the water
the duration of brewing
the water quality


However, speed of plunger may be important in this case: if you push the plunger rapidly, the flow of water push the grounds from the sides of the filter. Thus, the grounds will probably mix with the final cup of coffee. Even worse, the hot water may splash in your hand or face.