There's absolutely things that can be done that don't involve authoritarian dystopia. Access to contraception and family planning resources. Education. Better childhood healthcare. Improved rights and economic independence for women. Decreased tax incentives for having more children. Improved economic systems that don't rely on endless population growth.

Population growth in most of the developed world is already below replacement once you exclude immigration. So we've already arrived at a successful formula that solves overpopulation without limiting personal freedom.