Given the fact that almost of our clothing and bedding and such is colorfast, half plastic, and has been washed a hundred times already, why do we still sort whites and colors for washing?

I don't separate, I wash everything together. Of course the only whites I have are my socks and I don't care if they get some color bled into them.

Because not everything is colorfast. I had a nice white shirt my husband washed with his jeans. No I have a pale blue shirt. One of my pale turquoise bathroom rugs now has a funky red overtone because my husband washed it with a red shirt. I have now made a deal with my husband. He is only allowed to wash his own clothes. (We won't even get into how many of things have shrunk because he put them in the dryer when he shouldn't have. )