The world won't do anything until mass migrations start happening, wars break out and people become desperate. The rich and wealthy will wall themselves out as long as they can while we kill one another.
The rich are betting that they'll be the survivors to continue the species .... but chances are they'll just last a bit longer then everyone else and die out along with everything.
Humans survived and thrived as long as they did because they did things together. They won't last long if not enough of them are around. Especially in a hostile environment that we're definitely creating for future generations.