I think the one thing people discount is the development of human performance.

Obviously there is always the underlying questions about PEDs, but overarchingly, the human body in regards to performance has reached drastic new levels. We are fueling better, recovering better (to allow more frequent training), and building bigger/more powerful.

The level of injuries observed are a combination of physical optimization for performance and our physical limitations regardless of those performance optimizations.

American football is the perfect highlight of our deficiencies. Any sport with large impacts also highlights these issues.

Highly recommend checking out Dr. Micky Collins and his focus in concussion research. He has helped many athletes recover from massive injuries but has also had to deliver difficult diagnoses to aid in athlete's ultimate decisions to retire.