It really varies (pun intended). The linked pics are of my first sweater, now 15 years old. Done in cheap, variegated acrylic - it has been machine washed and dried a thousand times, has been covered with tomato sauce, cat fur and various bodily fluids excreted by our kids, but my husband still wears it (it's really soft and warm) and the cables are still standing up to the abuse. (I am *so* not a yarn snob!)
Anyway, I think the cabling shows up just fine, despite the variegation. And if I could find that same acrylic again, I'd buy it just for the durability. And I'd cable it again. I think the key is in the type of cables/texture - the close up should show you that these are quite bold, so they don't get lost in the colour changes.