True, but still exists scattering Mie (Gustav Adolf Feodor Wilhelm Ludwig Mie). I didn't go deep, it seems to be for larger particles?
Mie scattering applies to fog and clouds-- you'll notice clouds look various shades of grey or white, and the backscatter you get from white light in the fog is still white. (And with that scattering, a larger portion is scattered forward, not back, as it passes through the water droplet itself like a lens.) The reason clouds can appear orange/red in the sunset or sunrise is from the Rayleigh scattering through the longer atmospheric path the sun's rays take at sunrise.
As far as fog penetration, there is the concept of the "extinction coefficient" of light, and it has been studied to some extent with light between 360 (UV-A) and 2490nm (in the near infrared). It's been some time since I've read of the research, but generally speaking, the size of the water droplets in fog is such that the visible light spectrum will be equally scattered and have equal penetration. Really, the biggest problem with the backscatter in fog is how our own eyes deal with it. In fact, absent yellow fog lamps or yellow headlamps, wearing selective yellow glasses will have the same effect as using a yellow light source. It doesn't matter where in the 'chain' the yellow is blocked-- at the forward lighting or windshield or right at your eyes, you're reducing the "blue light load" on your eyes.