Why C94 lightning cable has silver pin not gold pin?

C94, C91 connector: The plating process is upgraded from gold plating to Rhodium and Ruthenium, and the gold finger appearance is silver.

The direct benefit is that the electroplating effect is better, and it is more effective to prevent sweat, liquid and the like from corroding the contact gold fingers, and it is more durable; in terms of cost, the process cost is more expensive than gold plating.