There has been a significant population level decrease in testosterone in men. It's at around 1.2% per year when adjusted by age.[0] Similar effects have been found in other countries too.
I think this is what he means when he says physiological.
That study had roughly 3k participants, from the Boston area. In my opinion, the are more than probably many factors that influence testosterone production and that’s not sufficient evidence to declare a population-wide crisis.
I think this is what he means when he says physiological.
[0] https://academic.oup.com/jcem/article/92/1/196/2598434