I think there is also another bias in the samples they have in that a lot of the older items have developed some sort of patina/rust/aging. That tends to skew t

I think there is also another bias in the samples they have in that a lot of the older items have developed some sort of patina/rust/aging. That tends to skew them in to the brown, dark grey and generally muted colors. If you watch the video there are a number of items that are old gears, chains and machinery.