We don't have the supply to fill the demands to simply throw all billionaires money into solving every crisis. That is why wealth inequality is so vast. Dollars are a made up system. In its raw form it's just paper. Backed by the govt. Where as it used to be backed by the gold standard which is why we hoard so much gold. That is a real tangible asset.
Paper is just paper its artifical, it's only good once spent. You can have infinite money if they forever printed it. Instead we balance inflation and deflation and finite supply that is dwindling the more we clear cut and strip the earth.