I always thought they were orange.

In the Minotaur household, we call the opposing team "orange people" and "the orange team" (or comparable).

if you really think that green berries are actually green you need to check again

and if political correctness is what you want then simply calling blue berries blue isn't enough as there is an array of classifications for the color blue that range from light to royal to many other shades and hues

calling someone a red or blue stems from old halo communities and even back then it stemmed from deeper roots even in martial arts there is usually a red opponent and a blue one

in fact correct me if I am wrong but green berries are actually more blue with a slight hue that makes it seem to be a part of the green color pallet but if you get down to primary colors and what all other colors stem from in terms of electronics we usually use RGB being red "gold" and blue each color usually stems from a mix of the former

but as to your original question and point yes there are color blind people playing dust, and no not everything has to make sense
also I do believe there is a colorblind mode but I may be wrong

in any case reds are reds because they are the enemy and blues are blue because they are allies, even LoL adopted this after having static colors due to the fact that the color of ones team does have a significant affect on the players and can cause battles to be wrongly represented with one color being associated with winning and or losing such as is the case in Ps2

red promotes hasty decisions/reactions while blue promotes a calm strategic approach. If your enemy was all blue you would be less likely to jump into a crowd of them guns blazing with core nades ready.... which is exactly how I play lol

It stems from closed beta, at the very beginning the teams were Red and Blue, however, color blind players objected and had the color shifted to the orange and "blue" we have now.

Altho I agree the colour is orange but I believe people say its red due to the colour red is a sign of caution or danger

Red is quicker to say than orange and sounds cooler. Though I'm fond of calling them pumpkins, particularly when they're getting smashed. But on here I usually call them reds/red dots cause they are the enemy just like the commies and those blasted red coats. I like to call squad members huckleberries even though those are actually blue.