Precisely stated as far as it goes. Unless Climate Crisis is addressed and action taken immediately - as in drastic conservation and carbon sequestering the scenario will be far worst than you state.

For example: resource wars over essentials such as fresh water, seeds, food distribution networks. Massive rotating power-outages some lasting for weeks, later months. New plagues from sources such improper care of animals, release of ancient pathogens (with no immunity from animals thawing from the melting of permafrost).

Drought, starvation, mass migrations... billions will suffer and die.

I am optimistic that about 1 million humans will survive in an agrarian based culture.