A lower birth rate means less workers. However the capital(factories, buildings etc) is still about the same. Therefore in a free market, workers should be paid more. In Western Europe there were two periods, when the wealth gap closed. One was after WW2, when millions died and the earlier one was after the black death.
childfree
this is why population collapses are surprisngly a good thing for workers after they have subsided because 1. it forces workers to be paid more even a little more since there is less people out there to work and 2. it gives a few workers the insight that Marx was rigjht, you shouldnt let the very rich and the politically connected bbe the ONLY ones who contrrol how much children you have . You should take a hold of your reproductive rights and produce less workers for them if the bourgeoisie make your life and youur loved ones' lives enshittified.
A society owned and ran by the people who do the most work (a dictatorship of the proletariat) is the ultimate andd only goal right now. By ANY means necessary .... 👀
If you want more children, foster an environment favorable to children. Austere policies and dystopian living is not fostering such an environment. Also, there is no “new land” on this third rock from the Sun (yes, I’m aware of volcanism but the state boundaries are more or less set unless wars happen). Getting and keeping Mars or any planetoid is extremely remote.