Look at the average life of a person living in Western Europe 400 years ago.
Look at the average life of a person living in Western Europe today.
Heck, look at the lives of the top 1% of humanity living 400 years ago.
From: https://en.wikipedia.org/wiki/Louis_XIV#Personal_life
> Louis and his wife Maria Theresa of Spain had six children from the marriage contracted for them in 1660. However, only one child, the eldest, survived to adulthood
From: https://en.wikipedia.org/wiki/Louis_XIV#Health_and_death
> Louis outlived most of his immediate legitimate family. His last surviving legitimate son, Louis, Dauphin of France, died in 1711 of smallpox and barely a year later, Louis, Duke of Burgundy, the eldest of the Dauphin's three sons and then heir-apparent to Louis, died of measles. Burgundy's elder son, Louis, Duke of Brittany, died of the same disease a few weeks later.
The king of France, arguably one of the richest people on the planet at the time, had 5/6 six children with his wife, the Queen of France and daughter of the Spanish King die before adulthood.
Now look at the life of an average middle-class French person (or American, or English person or any of the 6+ billion people living with electricity) today. See anyone dying in childbirth? Anyone dying of measles or smallpox before they're old enough to vote?
Technological progress, helping not just the rich get richer, but everyone get richer.
QED.