The author's claim is contradicted by his own numbers:

"According to the National Center for Health Statistics, life expectancy for men in 1907 was 45.6 years; by 1957 it rose to 66.4; in 2007 it reached 75.5. Unlike the most recent increase in life expectancy... the increase in life expectancy between 1907 and 2007 was largely due to a decreasing infant mortality rate."*

But with life expectancy at birth of 46 years and infant mortality of 10%, the life expectancy excluding infant mortality is still at most 51 years. So in fact we gained about 5 years of life expectancy from decreased infant mortality and 25 years from other factors.