Private companies also take extreme risks and fail. People running companies simply don’t face the same risks as the companies themselves. A 20% shot at 10x returns can be completely rational.
PS: Suicide is not just about shame, some people are simply in a lot of pain and seek a way out. Evolution did not optimize for joy.
I think we should retire that phrase and rethink it as the tragedy of greed. Many people are happy and even work to maintain some sort of equilibrium between their consumption and replenishment of natural resources. Garrett Hardin, who originated this trope, arguably had a very dim view of human nature and began with the premise that everyone was equally greedy and pseudo-rationally inclined towards maximizing consumption.