Wind and water make boating inherently more dangerous than staying at home. Racing adds risk due to extreme mechanical stresses frequently experienced. Stress can lead to equipment failure.
Racing also adds operational hazards from collisions, and amplifies the consequences of errors in handling sails and lines.
Inherent and operational risks can managed, but not eliminated. Accidents will happen. We can take steps to mitigate the consequences of some accidents. The simple precaution of wearing a life jacket reduces the chance of injury or death. San Francisco Bay is very cold. Even a strong swimmer can experience muscle paralysis after 5 minutes of immersion.