Too late for me to read this, but for those interested it seems to be a great article on the subject.
Conclusion: A Balanced View So, whats the verdict? Yes, some studies show notable declines in mens sperm counts and testosterone levels over the past several decades and this is a legitimate public health concern worthy of further research and action. No, it does not mean we are facing imminent extinction or that todays young men are half as fertile as their grandfathers in any practical sense. The reality is nuanced:
RFK Jr.s specific claim that a teenager has half the sperm count of a 60-something man is inaccurate in fact, young men have higher sperm counts than older men (age causes a decline). The comparison should be across generations at the same age, not youth vs elderly.
Even if sperm counts have declined, the average man today is not infertile. Typical counts are still tens of millions per mL. Fertility in the population hasnt collapsed; birth rates are down mostly due to later and fewer pregnancies by choice.
https://www.mensreproductivehealth.com/post/spermageddon-or-science-investigating-rfk-jrs-alarming-fertility-warnings