If we are talking about giving an example, while I agree in part, I also find there are people more popular and influential than billonaires. Half of the top 10 richest people are not really public personas at least from where I stand. Conversely, you do not need to be billionaire to produce 10000x CO2, you need some money but not that much. These people need to be also in attention focus. Even just middle upper class who like to fly a lot, the difference it makes is huge. Billionaires do their own part, but through ownership of large companies and their relation to customers, I think is more important way in which they make a difference.