The daylight between instituting a parenting license and eugenics is not very much.
And country after country has demonstrated how relatively easy it seems to be to reduce fertility. Iran is a not so well known example. Back in the 80s Iran started to feel that their fertility was a problem. Their population was growing far faster than they had the resources to sustain, so they instituted birth control availability and mandated 'marriage classes' [1], not entirely unlike what's being suggested here. And in these classes they worked to try to reduce overall fertility.
It succeeded far beyond any expectation. Their fertility went from 6+ to 2 in less than a decade. And then it just kept dropping. Today it's down to below 1.7 and it keeps falling. They've long since tried to reverse this trend and started an equal but opposite pro fertility program, but like China also showed - it's far easier to reduce a population's fertility, than it is to bring it back up. These sort of programs work as a perfectly viable proof of concept of a practically invisible eugenics program, and that's quite dangerous.
What you described is not eugenics though.
See, for instance, the famous quote from Supreme Court Justice Oliver Wendell Holmes Jr. that, "Three generations of imbeciles are enough." Interestingly enough, the ruling from that court case (Buck v Bell) was never formally overturned. It's simply that eugenics fell out of fashion, following it being taken to extremes by a certain vegetarian artist in Germany with a knack for rhetoric.
For example — we don’t particularly need to do anything to reduce birth rates of technologically advanced societies societies with human rights. That’s because women choose to study and work on their career in their 20s, while men try hard to save up to afford the sky-high real estate prices. The market does the eugenics for everyone.
If anything, the fear that uneducated populations or those in low-cost-of-living countries are going to “replace us” is a result of that simple fact. Comparing continents, Africa is expected to continue to have a ton of kids per woman compared to, say, Europe or USA.
Religion, of course plays a role. When the condoms are off, the religion doesn’t matter — you’re going to have a lot of babies. The only difference is, how early do you get married? Religions tend to frown on premarital sex.
Fertility is most strongly correlated with child mortality IIRC. The more likely your kid is to die young, the more likely you are to have lots of kids. Very low child mortality in developed nations, so very low fertility.
Other than the hard work put in to scaring would-be parents. Indeed, the birth control pill put people in control, but it it is only since the "16 and Pregnant" movement, which campaigned on demonizing having children and stressed the importance of not being saddled by a child, that we've seen below replacement levels.
As a result, the youth of today in their prime rearing years look negatively upon having children, and by the time they "snap out of it" they are into their geriatric child birthing years and biologically don't have much time left, putting tight constraint on how many children can be birthed.
> That’s because women choose to study and work on their career in their 20s
Trouble is that, thanks to the same campaigning, those who choose to have children in their 20s (or earlier) have to face the scorn of society. Unless you are strong-willed, you have little choice but to study and work on your career, even if children is what you truly want, because everyone else is going to try and make your life miserable if you don't.
Drawing an equivalence between these two is like saying a school system that punishes mistakes with physical abuse as a matter of policy to make a smarter population is identical, morally speaking to society at large, as a school system that just rewards good and hard work as a matter of policy to make a smarter population.
It makes no sense. I can't believe anyone could actually believe rewarding parents who have demonstrated a commitment to rearing a child well is identical to enforcing undesirables not have children.
I think you could also make an argument in reverse here as well. An increasingly large chunk of Western advertising is actively seeking to push values like contravening said genetic proclivities, yet it seems to have had little to no impact on what people find attractive. That's even more telling as obesity is rapidly becoming the norm rather than the exception.