Every generation that has a 1% annual rate of economic or population growth at the end of 30 years has about a 33% per generation increase. The law of accumulation is ignored by the ignorant. Over a century the increase is thousands, and that law of accumulation applies to demographics as well. Thousands of times of increase on Earth-like planets without a capacity to provide even a fraction of the natural resources. When we will build a new world of Earth size some day we may begin with a construction population of 10 billion yet soon thereafter reduce population for the new planet through measured one birth per family for a few generations to the normal carrying capacity for an Earth world of two billion. Some of the extra population may relocate to construct another world. It is normal that each new world has an optimal ratio of humans per surface area for production and a healthy ecosphere simultaneously.
Populations cannot achieve zero population growth static stability then experience a flood of immigrants to replace them without causing more damage to social infrastructure and the ecosphere. With a calm draw-down of population growth while technology and education of the masses increases, world ecospheres could be directed to recover and new opportunities for building off-world ecospheres explored. It is important to begin building terrarium ecospheres with as much wildlife from Earth-like worlds as possible to improve the art. Innovative ideas for moons and planets can bring new ways of letting life flourish including new human populations intelligently designed to be in appropriate numbers for the new ecospheres.
Adroit political management rather than coercion need be the political method for stabilizing human populations as it bides its time before increasing again in new ecospheric regions it learns to build. Those ecospheres should be as robust and teeming with life as that God gave unto mankind rather than depleted of it. There is a time to grow a population and a time to hold fast or even decrease. Sometimes, fortunately rarely for politicians, conservative, sober rectitude is requisite for species survival.