That's the problem with saying "people should have less children". Yes, they should, but the people who will listen are often the people best equipped to raise

That's the problem with saying "people should have less children". Yes, they should, but the people who will listen are often the people best equipped to raise children. If prosperous, well educated people have less children (who we can assume will end up better educated) and poor people have more (who we can assume will not receive those opportunities), that will only increase the imbalance.