The important point here is that there is not and cannot be anything prescriptive about a scientific theory. It's merely an attempt to observe and explain. Darwinism tells us, in simplified form, that lifeforms which are less successful at replicating themselves than other will leave less copies of themselves around. This is just common sense, as Darwin himself pointed out several times.
Darwinism does not say it's good to reproduce, or that the purpose of life is to reproduce, or that things are progressing to some ideal, or that there are some things we should try to select for in humans. None of the above can be derived from what is just a description of things happening.
To give an example, we could observe that some selective pressure is causing people with big noses to have more children than others in some society, and that their children are just as likely to survive and prosper as the average. Darwinian theory will tell us that, as long as that selective pressure remains, the proportion of population with big noses will increase. It does not tell us that big noses are better than small noses.