I for one need a challenge to be at my best.

I guess you could say humanity has become too successful at evolution, because not only have we survived all the harsh dangers of the wild, we've limited them and in many ways annihilated them.

Our average lifespan has vastly increased because of it. In the old days, diseases and fatal infections after being wounded would be the biggest danger I think. Any open wound might infect (and likely would) and poison your blood if not sterilised, something we take for granted these days. Medical science had been more harmful than helpful for quite a while.

Our highly developed medical advances and level of education has vastly increased our chances of survival, in an evolution way of thinking, probably too far.

Back in the day, only survivors would be able to remain in the genetic pool. The weak/dumb/unlucky would not survive long and have a lesser chance of spreading their genetic heritage. In the past, if you had a semi-serious accident, you'd die. Now you walk out of a hospital as if nothing happened.

As a whole, especially the western world, has grown soft. Does that mean that if something really bad would happen, humanity would die out? I think not. For instance, if a global killer meteorite (like the Dinosaur killer) would strike, a select elite of people with a survivor mentality would fight and survive.