The obsession with colour isn't about the colour. It's indicative of the general obsession in MMOs with gear quality. It has been like this since the dawn of time and always will be as long as gear is the primary means for character progression.
You get rid of colour, people will obsess about the item level again, or some other means of rank. Making superficial changes that don't really mean anything just because people have the wrong attitude is sort of a silly approach.
On top of that, it would remove the times when the colour is actually useful for evaluating items. The grey name is a very quick way to know an item can be safely vendored. A brown item is something you know you can mail to alts. If you find something orange, you know you've got something really, really special. And you know when a green drops in a dungeon that you probably don't need to plug it into your spreadsheet.
Finally, people care and obsess over a lot of dumb things, both in and outside of the game. The appropriate response is to realise those people are silly or misguided or exaggerating, not to remove the thing they're focused on.