This is not the case because, using the color picker, here are some of the values I get when I select the blue areas:

#7a85a1, #8393b7, #858bab, #7287b6

In RGB (Red, Green, Blue) this is:

(122, 133, 161), (131, 147, 183), (133, 139, 171), (114, 135, 182)

As you can see, the third color component in all of the samples above is by far the highest; that's the blue component. If it had been white, all the color components would be approximately equal.

For the color in the lower part of the dress (the last sample), the blue component is over 34% stronger than the next strongest color (green) and almost 60% stronger than the weakest one (red)!