Hair matters to most women (as in being a plus). Its simply a fact, conscious or not on their behalf.
Yes there are some exceptions (the 100% inevitable sean connery example always gets cited lol) but for the most part having hair helps, both with the pure virility/youth aspect to women, as well as from a confidence point of view.
To use a celebrity eg. Chicks used to wet themselves silly over a young jude law. Now that he's almost a baldy he gets roles as the wronged husband and 'best buddy' (sherlock holmes)