the book "limits to growth" from the 70s has a bunch of discussion around potential future trajectories for human population, based on modelling & simulation.
the authors discuss & model different interventions & policies that could be put in place to try to prevent the "overshoot and collapse" type scenario where human population peaks and then crashes.
a lot of the critique of the "limits to growth" modelling is of the form "a crash in global population was predicted by time T, but that didn't happen", but the modelling doesn't really try to make predictions in terms of specific events happening at specific timescales, it's focused on understanding the underlying behaviour based on the structure of the system.
the authors discuss & model different interventions & policies that could be put in place to try to prevent the "overshoot and collapse" type scenario where human population peaks and then crashes.
some academics argue that things are tracking somewhat consistently with projections of the modelling from 50 years ago: https://www.theguardian.com/commentisfree/2014/sep/02/limits...
a lot of the critique of the "limits to growth" modelling is of the form "a crash in global population was predicted by time T, but that didn't happen", but the modelling doesn't really try to make predictions in terms of specific events happening at specific timescales, it's focused on understanding the underlying behaviour based on the structure of the system.