The concern for disruption of the ozone layer was real. action was taken to cease the use of fluorocarbons 25 years ago, to some extent restoring the natural balance you are describing. I don't think the cycle you are describing was unknown.
I doubt if NASA would agree with such statements.
Are some scientists "cooking the books" to dispute the generally accepted scientific reports of climate change & gain approval & funding from Trump? Global warning is now generally referred to as "climate change." Man's activity is significant leading to the rise in atmospheric carbon dioxide.
There was a real concern about global cooling in the last quarter of the last century, based on historical recorded temperature cycling, & observations thank indicated that possibility. However there was also an awareness of the potential for global warming based on human activity particularly increased CO2, smoke & dust.
Most nations are concerned with the fact of climate change, though the willingness to take national action varies. Isolated factors are significant. Deaths & ill-health from pollution in cities due to coal fires were very serious. We couldn't eat apples from our west London garden. The introduction of smoke control laws & subsidizing non-polluting heating systems improved air quality massively & we could enjoy our apples.