The irony of course being that regardless of whether or not one believes in the principle of finite resources and/or carrying capacity, the expression and apparently wide-spread holding of such views is an immensely strong argument against individual choice in such matters, and for some collective mechanism of restraint. Not necessarily coercive, which has proved both unpopular and controversial, but perhaps based on nudges, norms, and opportunities for alternatives which don't inherently penalise cooperators and reward defectors, as illustrated here.
Historically we have had nudges, called inpatient parents, uncles, and aunts. Whether we need to keep nudging in that direction or the other one depends very much on what you think the carrying capacity is.
Worse demographic ratios though which I think is likely more important.