It is recognized that breeds have very distinct personality types. For example Siamese cats are extroverts and sexually precocious and this trait is passed on to other Orientals which are basically Siamese cats in disguise. It may have been introduced in a roundabout way, but ultimately the pattern traces back to a Siamese-type ancestor even if it was introduced a few generations ago from a Birman or Himalayan. If the colourpoint pattern has managed to be passed on through many generations and matings, it is not impossible that some personality traits have been passed on alongside it. Russian Blues and Korats are both quiet breeds.
Research suggests that colour has a strong influence on what cat people choose.
Superstition also plays a part with black being considered lucky in some parts of the world. In North America, black is unlucky. In various countries different colours are considered lucky or unlucky and this affected the colour make up of cat populations as bad luck colour kittens were destroyed. In the 1960s in London, there was a preference for ginger cats or ginger bi-colours. In 1975, a study in Glasgow found that suburban residents in the city preferred cats with ginger or partly white coats.