Eh, there's a difference between will and can, and it's pretty apparent that global climate change can bring about the conditions of the collapse of humanity. Crop growth zones are shifting and shrinking, climate change means more extreme weather, which results in more crop failures as land suitable for large scale agriculture shrinks. Sea level increases result in more salt water intrusion into groundwater, the Atlantic Meridional Overturning Circulation (AMOC) is likely to collapse in the next 70 years, which determines the weather from the equator to Europe, crop production in Africa, and sea level rise on the east coast.

Warmer waters spawn more tropical storms and hurricanes, resulting in more lost crops and infrastructure damage in the south east, an entire years crop of Georgia peaches was lost for the first time after multiple weather impacts. Temperatures in areas unmoderated by large bodies of water are becoming so hot that human habitation is approaching a cost that is untenable across much of the southern US.

At any rate, its not like the sun is just gonna scorch us off the planet, but there are a thousand little things that could collapse international food production, kick off famines as developed nations buy up international supplies, spark conflicts as large populations start migrating from less habitable locations, and nations begin competing for newly limited resources. I'm optimistic that things can be resolved, but we're expecting agriculture production to shrink, waters are already overfished, and animal production relies on agriculture. Enough bad decisions and we can turn a series of collapsing supply chains into a post apocalyptic thriller.