Honestly some don't. I've seen quite a few dudes in my university with sh*t hair who don't offer anything else (not masculine, rich or exceptionally smart) and have a great looking girl by their side. That being said, it also depends on the culture. I think baldies have it the worst in the US. In EU i don't notice it being that bad. With that being said, most women consider hair a big plus, of course.
His good facial features can compensate for his hair loss until nw3 without any negative effects. It is a different story for average joe. Many start getting invisible to women starting from nw2.
all that matters is your physical attractive qualities and hairs add a huge points in it. if you are a male with average characteristics, lets say, 5'11'' height, fit body, decent looking face but still have luscious hair then that will make you attractive and hair matters in this case. but on the other hand, if you are 6'2'' tall, well build and sharp jawline then it will make up the cost of not have hair.