As I understand it, the colour isn’t that important. Camouflage is more about breaking up the shape (and lets face it, if you can’t manage to get your green uniform looking grey/ochre within about 5 minutes in Afghanistan, I’d be surprised).
Semi-random splotches do work about as well as anything else - depending on how far away you are.
The large splotches that used to be used are fine at a distance but pretty obvious close up. Small splotches blend into one at a distance. The digi stuff is supposedly designed so that it works at a range of distances.
It’s also a lot about fashion as JonS says above.
