Face color after subtraction

I have two objects and want to subtract one from the other. I typically have each object its own color to keep track of what things are for. The annoyance I have is after the subtractions the object that has been subtracted from becomes the color of the object I was using to subtract.

I guess the easiest/intuitive way I can think of is the new face after subtraction should inherit the color of the body it becomes a part of instead of the part it came from.

It would be really great if the object that was subtracted from could keep its color instead of inheriting the color of the removal part.

Here is an example. I have this bi-stable compliant system I am working on. I use the blue-ish color to indicated flexible material (TPU S95) and the white to indicate rigid material (PETG). After I subtract the blue flexible area from the rigid, the rigid part is now blue instead of white at the intersecting points.

I am sure this is a low priority issue but if it is an easy fix it would be great.