This is not so. Red is a known color of Porsche caliper and so is yellow . Each represent the type of brakes on the car. Porsche happens to offer gloss black for either of those two in case the person feels that the natural color doesn’t look as well with the exterior. A base model car doesn’t get either red or yellow unless the person were to option it specifically with those brakes. PCCB are not even available on the current generation Macan, but they were available on the first generation, which was the OP‘s car. We have a few members that have them.
As far as painting, the caliper in some type of non-authentic color goes any person who knows Porsche will immediately see that . Whether they judge or interpret, it will differ from person to person.
When it comes to cosmetics, it basically is up to the owner what he wants to do. Of course he can paint a mural on the side of his car of an elf dancing on the moon if he wishes. It doesn’t mean everyone will think it’s great.