Mostly because people are fatties and eat unhealthy food from plastics and take opioids.
Obesity is highly correlated w low T, as is poor diet and opioid use. This is all well established but you can’t have anyone take personal responsibility these days.
You can naturally increase T levels by exercise and weight training and healthy common sense eating but most people are too lazy and want instant results. I see many of these types in my clinic. you can go anywhere and have a ‘doctor’ prescribe you TRT.
RFK taking TRT is the ultimate irony…he rails against big pharma yet is one of their premier clientele.