That is not true. First of all, your definition of natural selection as favoring beneficial adaptations is not the standard definition of NS which is survival of the fittest based on the Malthus theory of conflict.
Second, humans are evolved natural creatures, so evolution applies to us just as it applies to others.
Third, Darwin took Malthus' human population theories as the basis for his understanding of NS and applied them to all other living beings. If they do not apply to humans, what evidence is there that they apply to other living beings.
So it doesn't matter if dark coloration doesn't help a moth find food. If it gives a moth an advantage in avoiding predation, or in successfully mating, it is a beneficial adaptation and it's still an example of natural selection at work.
Maybe we are getting some place here. You take several changes, such as the ability to hunt for food, to hide from predators, to find a good mate, to avoid disease, and put them together as beneficial adaptions. Thus changes that help the organism are beneficial adaptions and are the product of Natural Selection.
I hope that we are agreed upon the fact that Natural Selection selects in new beneficial adaptions and selects out adaptions, which are not beneficial. There are many traits which are neutral, in that they do not affect the overall fitness of the organism. These are selected in.
The primary question which is not properly answered is what makes an adaption beneficial or not. When we use the traditional understanding of evolution to answer this question, we have circular, non-falsifiable thinking. Change is caused by conflict. If the adaption caused the lifeform to win the4 conflict, it is beneficial, if not it is not.
On the other hand ecology and symbiosis says that change is cause by ecological changes which take many forms, but primarily climate change. A beneficial adaption is therefore a change that allows the organism to better adapt or live in its environmental niche. Conflict therefore is not an issue and indeed most adaptions result in the mutual benefits for the organisms involved.
The Peppered Moth story clearly illustrates this. A change in the environment cause the moth to be more vulnerable to predation. A color change fixed this for the effected moths. Another environmental change reversed this process.
Climate change slowly caused the habitat of the dinosaurs to disappear and finally become extinct. An asteroid hit hasted the process that still took many years, not by mass slaughter or suffering beyond that common to life. This opened many new niches for mammals and the bird dinosaurs, which gradually filled them and diversified life on the planet.
There was a big study that confirmed this process which took place a few years ago. Punctuated equilibrium is punctuated by important ecological changes. Ecology guides evolution and explains the changes from relatively simple single cell organisms to the complexity and diversity of today.
This is the science and the science also confirms that life is unified and not random, haphazard, and nasty.