I‘m not bald but I think your view on that matter is very simplified and a bit shortsighted. Healthy hair is a big contributor to the perceived attractiveness

I‘m not bald but I think your view on that matter is very simplified and a bit shortsighted. Healthy hair is a big contributor to the perceived attractiveness of a person, which in turn can have a big influence on the career success of a person (numerous studies proof that). So going bald can severely limit ones career options and/or negatively influence the currently chosen career path. Personally, as a more drastic example, I think a bald(ing) person would have harder to become US president than the same person not bald(ing). Also shaving your head definitely is not an option for everyone. You have to have a very well proportioned head and normal looking ears to make it look acceptable or even good. So balding can also severely influence your perceived sexual attractiveness and limit your options for mating. I think its not just superfluousness or as you state an "idea […] socially constructed by the mass media and advertising industry" that make a number of men who are starting to bald also getting depressed. It might be just the realization of some of the things I stated above and/or other factors, which I would not dismiss so easily.