ES,
Many of us consider Genesis 6 to mean that the life span of humans to be no longer more than 120 years.
There is historical evidence that, life expectancy has increased significantly with the advent of chlorinated water, vaccinations, and antibiotics. None of these should be abused or overused, but they do save lives.
Genesis 6 is post judgment, but many still lived much more than 120 years after that.
I suppose for the few that were drinking bacterially polluted water, mild chlorination might have increased some life spans, but the contrary is true for those that have clean water. Sanitation is the mark of an enlightened, and Godly society, to be sure.
I haven’t consumed chlorinated or fluoridated water for over 40 years.
.