I really doubt that. While I am aware of shrinking IQ, as far as I know its a thing of the last 30 years, leaded gas in most developed countries was already outlawed.
Perhaps when we finally translate "unintelligent people" into "vermin" we'll do what many previous iterations of society have done... genocide.
Part of this is literally possible. A big part of made stark to point out that we should be careful in the way our language dehumanizes people of below average intelligence. They're still part of our species, and biological history.
We can't let the ghosts of eugenicists past scare us away from asking important questions. Avoiding the awful mistakes of the past will require care and diligence, and can be (must be!) done without embracing the easy path of reactionary "moral" ignorance.
I honestly think part of it is like Parkinson's law, but for resources to spend on children -- Children are expensive to rich people largely because rich people spend lots on their children. (too much?) Children mostly thrive in opportunity and resources (so long as it isn't pacifying their desire to achieve for themselves).
On the tradeoffs, this is pure psychology. Generations of people who have shirked social responsibility, and maximized selfishness. "Me" generation + "me me me" generation and all that. Time for people who see society, humanity, and duty as more beneficial than getting a bunch of likes on TikTok for doing something that inconveniences others (like dancing in a crosswalk or something) .
200 ok /Rant