Unfortunately, you're simply failing to grasp the scope of the problem.
You're quite right that poverty is the biggest killer on the planet, but poverty is also the primary reason why people will die (and already are dying) due to global warming.
You see, when a system of oscillators accumulates energy, the amplitude of the oscillations tends to increase. This means that the extremes become more extreme, and you get both extreme droughts and extreme floods. Haven't you noticed that Texas and Arizona are burning while the Mississippi floods? That sort of thing starts happening much more frequently as the temperature increases.
So it's not just a matter of being slowly inundated by the encroaching sea, it's more like being alternately inundated with record flooding and parched with severe drought, repeatedly for many years, and then being slowly inundated by the encroaching sea.
You are fortunate that denial is, as they say, not just a river in Africa, because when the rivers of Africa start to experience alternating severe drought and flooding the way Australia already is, you're probably not going to want to be clinging desperately to any African rivers anyway.
So, what effect do you suppose all of this will have on food commodity prices? And what effect do you suppose that will have on the poor? It's already happening, food prices are way up and many people are dying because of it. And this is only the beginning, Mother Nature is just getting warmed up.