Ignoring Opportunity Cost & Limited Resources
A comet could be on the way now that we don't know of that could wipe out humanity in a year or more and we not know about it yet. Odds are low however. A far more distinct possibilty is that our civilization is nearing a technological peak due to limited resources. History is littered with fallen civilizations caused by war or resource limitations. Both of those possibilities look like near term worries. I'm all for giving our eggs more than one basket and the equivalent of a back up copy.
Regards,
Mark