Better to encourage it then, surely. If rich people are doing good things in order to win praise, what's the point of denying it to them? If enough of us react

Better to encourage it then, surely. If rich people are doing good things in order to win praise, what's the point of denying it to them? If enough of us react that way, we won't diminish the power of the rich people, we'll just get to watch them spend their money more selfishly. This doesn't mean staying silent about the bad things they do. But if we only respond to the good things by bringing up the bad things, we end up perversely being more critical of the ones who do some good, and diverting our scrutiny away from those who don't even bother. (I haven't looked into this pledge, so I'm just speaking on the hypothetical case where it is likely to do good, as you've acknowledged is at least possible.) edit: I just noticed that you say in another comment you 'do not believe in climate change'. In which case I guess this line of reasoning won't have any force for you. But maybe you can understand why people who do see climate change as a serious problem are going to take a pragmatic view, and treat the investment of $10b as vastly more important than the lifestyle sacrifices of a single person.