Every individual that we "allow" to live is another person that could theoretically come up with a life-altering creation, poem, event, etc. Possibly.

But perhaps you have stumbled on why we have risen to rule the world - instead of leaving those behind that are physically weaker than the rest we help them, we find a place in the world where they can still function, and we make sure that we do our damndest to keep our herd whole.

Personally I find that to be one of humanity's biggest strengths, the ability to care for one another.