As white is not really a color I guess what they mean is you can mix green, blue, red or whatever, but I wouldn't wash a white shirt or boxer with colored clothes.The only white I'm wearing is my underwear and I wash those at higher temps than I can use for colored laundry.
my white shirt is still the same white as it was when i got it, not fading into another color or discolored, and i wash all my clothes in one batch, mixed with red, blue, yellow, green, black, etc
but as puma and creative said, it’s likely due to modern techniques in dying clothes or with better laundry detergent, because a decade back, my clothes got discolored from my mixed colors-washing
I think never mix a red with a white if it's the first time wash but after that everyone gets to know each other in the washing machine and it's all good
Not so much about colors anymore rather than fabric. Some can handle harder settings or even higher temperatures. Combine jeans and towels, separate wash delicates, and everything else can go together
but as puma and creative said, it’s likely due to modern techniques in dying clothes or with better laundry detergent, because a decade back, my clothes got discolored from my mixed colors-washing