In the past four decades we have murdered over 53 MILLION Americans and when you consider that a large portion of them would have since had children, we have probably lost close to 100 MILLION people who would be consumers, investors, workers, taxpayers, etc. This has nothing to do with any health/wealth gospel, this is about the real consequences of population control and these consequences are compounded by the fact that we have programs like Medicare and Social Security that require predictable population growth.
I have no quibble with you saying that a failing family core/social structure etc. will then lead to changes in values/loss of other morals etc. that ultimately could bring us down. It happened to Rome and could happen here.
It already has happened here and hopefully it's not to late to rectify the situation.
Or doctors, scientists, inventors... Perhaps one would have found a cure for cancer, lupis or some other currently incurable disease.