Gotta say, SRAM's been doing oilslick for awhile and this is the first tantrum I've seen about how it wears. A few ppl with some minor grumbles about cassettes with black finishes looking dingy, but nothing at this level.
Sure, I'd rather have a plain "silver" cassette (and the 10spd cassettes I buy for my gravel bike are always plain silver), but in their infinite wisdom, Shimano decided to make all their 12spd cassettes with black alu cogs. they get scratched up with use. but the dirt/grime kinda covers that up. so my lesson is not to wash my bike so much.
Ano has a tendency to rub off in high wear spots, too. Crank arms will do it where your shoe rubs. ODI grip clamps will do it, too.
Colored tires, saddles, and grips get dirty and stained to the point that they never look like new. White saddles get that way REALLY quickly.