No were not. Average Life Expectancy (ALE) is the metric that says we live DECADES longer than people from a hundred years ago. But you are using the wrong metric.
See ALE includes infant mortality rates that have plummeted. Because more infants life to adulthood, that raises the average. In addition the infants and children dying before adulthood never paid into SS.
A better metric is to look at months that benefits are drawn. The average increase (using male and females) is about 4 years longer. Not decades.
WW