All very interesting.
It is true, over many years people said we were one bad harvest from
disaster.
It was true then but it did not take into account the effect of cheap oil had on food production.

There is a very telling graph I have not been able to find again.
It displays two traces, world population from about 10,000 BC and
the production of oil. The world population varied only slowly from
the invention of agriculture to the start of the industrial revolution
and the use of coal and oil.

From that time on oil production and population track exactly.
The energy content of oil is so great and it was/is so cheap that it
enabled cheap food.

As oil depletes at say 4% per year then world population will fall
at 4% per year. This rate will be lessened to some extent by
alternative energy sources. However the energy content of oil is so
high and so cheap on the upslope that nothing will compare on the
downslope to make more than a small difference in the decline rate.

Now if you want to worry about how that decline in population will
occur I suggest you look at the Tunisian vegetable seller and all that
has happened since.
If no more babies were born, the world population would decrease at
just 1% per year.
The difference will be made up of starvation, malnutrition and wars
for food and resources. If anyone thinks we can negotiate a way out
of this dilemma I would like to hear it.

Global warming will not be a factor anyway as the transition that will
occur is much more powerful than any campaign to reduce CO2.

Just in case you are foolish enough to think this is away in the dim
distant future peak crude oil was in either 2005 or 2006.
Depletion now looks to start sometime in the next five years if you
are an optimist.