I’m also convinced that the math behind what is called “chroma preservation” is not correct, or at least the current math is not providing what AFAIK is the intended goal, that is to preserve the original chroma and hue of the colours.
I have tried to explain this in the past, and proposed a possible solution. You can see the beginning of the discussion here.
@paulmiller also arrived to a similar conclusion (see here and the following comments from him).