If the contrast level drops the colours will be washed out – like pouring water into a glass of red wine.
Without black (i.e. darkness) there would be no colours.
The actual balance of colours in a given light source is described as the colour temperature measured in degrees Kelvin.
Pure white daylight has a colour temperature of 5600 Kelvin whereas standard TV studio lighting has a colour temperature of 3200 Kelvin. The lower the colour temperature, the greater the dominance at the red side of the spectrum.
To some extent the eye adapts to the colour temperature, which is the reason why we still perceive white as white even though the colour temperature has changed.
A typical example is the eye’s adaptation to standard light bulbs, which has a low colour temperature, but we still perceive the colours almost as we would in pure white light.
When comparing the two different “whites” and perceiving the colours simultaneously, the low temperature “white” is clearly reddish or yellow compared to the pure white.
The phenomenon is clearly visible when using a daylight film to take photos indoors with normal light bulb lighting, because the film does not have the capability to adapt to the colour temperature.