It's a byproduct of (poor) restoration.
Fabric type does not change how film renders color. RCA was not trying to promote color receivers with oversaturated colors in the programming; they had enough trouble building cameras and receivers that performed consistently.
Film stock of the nineteen-sixties was easily able to accurately render lime green and lime green and gold as gold provided that the cameraman and the lighting director knew what they were doing.
Color TV was as new to production crews as to audiences. Directors tried to get images that looked "natural" on the equipment at their disposal, in some cases all production was done in film, and viewed as film. The color movie production standard was to err on the side of oversaturation, because film stock colors dilute during projection and fade with age. (Acetate film stock also tends to yellow as it ages.)
What was not capable of accurate color rendition were the color cameras used in the film to video conversion and the television receivers. Decisions on what colors should be used for costumes were modified after it became obvious that the original colors did not render well through video.
Variations in custom colors and spots skin tone are due to bad restoration technique. Leonard Nimoy's makeup had a faint green tinge to it and was supposed to render that way in contrast to William Shatner's slightly ruddy makeup. If restorations had been done from film, and directed by someone familiar with the original series, it is likely that the colors would look significantly different everywhere,not just the costumes, the actors, the scenery, everything.
If you look at the backgrounds of the restorations now being broadcast, you will see that all foliage is tinted toward cyan, less yellow, more blue than natural, while all flesh tones have been muted and normalized. This is the result of subjective decisions, not technology.
At the time Star Trek was produced, no one dreamed that the programs popularity would endure, that the series would be a cash cow for decades. It endured not because of the technology used to produce it, but because if the future it tried to portray. The special effects and stilted acting style of the original series are laughable today,but were acceptable to the less sophisticated viewers of that time. What endures are the relationships between the characters and the values and attitudes they portrayed. They showed our better natures becoming norms, not ideals.