Has modern medicine ensured longevity?

Has modern medicine ensured longevity?
We often hear the argument that modern medical interventions have drastically increased the lifespan of populations. This claim has been doubted in many studies that studied the decline of diseases that afflicted the populations from the onset of the industrial era in the 18th Century to early 20th Century.
First of all, it is injudicious to compare the lifespan of populations in an era that was characterized by mass exodus from villages into towns drawn by the prospect of jobs in industries resulting in acute shortages, most squalid living conditions in urban ghettos and a period that also saw two quick World War's that killed and also sapped the vitality of people.
Study after study has found that the diseases preying on populations in this era were stemmed by mass movements that led to political interventions and resulted in access to better housing facilities, access to clean and fresh water, access to fresh nutritious food, better sanitation & hygiene, better wages and working conditions in industries, the emergence of a much protested movement that led to practice of hygiene among physicians and nursing, diet, bed rest and isolation of patients (practices that were established due to the efforts of Dr Christian Samuel Hahnemann, MD), and better care of pregnant women and new born by trained midwives through home deliveries.
Researchers John & Sonja McKinlay showed that "..medical intervention only accounted for between 1 & 3.5 per cent of the increase in the average life span in the United States since 1900." Yes, just 1 to 3.5%.
It has also to be considered that there has been an explosive increase in serious chronic disorders leading to a chronically sick population - afflicting both the very young and extending to senior citizens. The Global Burden of Disease Report 2016 clearly points out that chronic illnesses have become the new normal. "People are living longer but are suffering from not one but multiple chronic disorders". This trend was also noticed and commented on in the studies referred to above.

The Questionable Contribution of Medical Measures to the Decline of Mortality in the United States in the Twentieth Century

The Cruel Deception

Dissolving Illusions: Disease, Vaccines, and the Forgotten History Paperback – 27 Jul 2013