It's an interesting take. I'm sure it's true for many of the men on this forum.
I have been blessed that I never took any of my identity or confidence in my hair. I had extremely thick hair as a child (to the point that my barbers always expressed envy), but I never took any pride in that. When I was playing football in high school, I hated the feeling of matted hair under my helmet, so I shaved it. I found out then that I really liked the way it felt, regardless of how it looked. When my hair started receding and thinning on top in my early 20s, I made the decision then that I would keep it until 30 and then go sly (although I didn't know that term at the time). When the time came, I stuck with my decision and I've never looked back. I love being bald, and I definitely think I look better sly than I did with thinning and receding hair.
Whether you are a Christian or not, this verse has a lot of truth and hopefully can bring some comfort:
For you created my inmost being; you knit me together in my mother’s womb. I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well - Psalm 139:13-14
And for the secular argument, while I have mixed feelings about the overall theme of the movie, the famous Fight-Club quote always comes to mind when I think about the way people struggle with this issue.
"You're not your job. You're not how much money you have in the bank. You're not the car you drive. You're not the contents of your wallet. You're not your !@#$%^& khakis" - Tyler Durden
I would also add, You're not how much hair you have on your head.