Now you know why countries flags have this kind of colors:)
Where on Earth did you get this idea? There is no reference link to justify this; all I know is the colors are based on the preference of who designed the flag based on the culture, history, and the prevailing condition of that time, and these conditions are changing.
And all the people of one's country are diverse and cannot be generalized; you cannot have one country and all of them exhibit the same character.
The colours and designs of national flags usually are not arbitrarily selected but rather stem from the history, culture, or religion of the particular country. Many flags can be traced to a common origin, and such “flag families” are often linked both by common traditions and by geography.
https://www.britannica.com/topic/flag-heraldry/National-flags