I'm thinking at least 4 billion people will die from bad water, bad air and no fish in the ocean this century

As more people die the remaining people become more desperate to survive for themselves and their families. This will tend to collapse (especially 3rd world governments) in the process of all this happening worldwide. This will also cause more and more species to die out from over hunting or poaching and the largest predators likely will go extinct (possibly including humans) by 2100.

As more people die, the richest nations like the U.S. and possibly Europe will not report much about the increasing deaths in 3rd world nations (sort of like now) because it is too embarrassing for them to not be doing something about the ever increasing deaths caused by Global Warming which is caused by Greed of the wealthiest on earth.