Modernity was essentially built by consistent 2% global population growth from 1950-1990. Currently world population growth is 0.7%. Once population growth becomes negative(in the next decade), the general moods will be very negative, with economic growth being much slower too. Things will broadly improve, but it will be very recognizable, and we won't go through any of the transformative changes our parents and grandparents lived through.
There will less demand for hydrocarbons and food though and adding in increased productivity, so poorer countries should find it much easier to get by in theory.
There will less demand for hydrocarbons and food though and adding in increased productivity, so poorer countries should find it much easier to get by in theory.