the richest 1% consume about 15% worth of total GHG emissions (when counting consumption).
The gains from all those 1% (globally) becoming... minimum wage workers would be a 15% drop in GHGs. Which would be a very good chunk, but not enough. One billionaire is unlikely to even be responsible for 1% of the total. I imagine that the rocket assholes could rank up on GHGs if the decide to commute every day from a private space station, but I'm still not sure that one or two of them would reach 1% of the global GHGs.