After demographic alarms went off when Chinese mothers had fewer than 10 million children, how critical will the situation become if only 7 million are born this year?
Basically an aging population makes it hard for a country to find replacement workers for its economy, which results in stagnation. Takes more than a couple of bad years, though.
That's true in extreme circumstances but we're no where near any threshold for having a lack talented people willing to work for a fair wage.
I can't recall the exact timeframe but the world's population has doubled in the last few decades. I'm not advocating for removing anyone but if we could slow down the making of new people that would benefit everyone.