Once someone has a billion dollars do we really want them to continue accruing more wealth (power)? Isn't billion dollar people and companies unduly influencing our government the source of many of our problems?
No, it's not; the people complaining that billionaires are the source of many of our problems cause more problems than the billionaires do.
Seems pretty evident that once you get beyond that point you stop considering regular people fully human, and start doing crazy things like threatening to destroy entire civilizations or buying and selling children.
You don't "have" a billion dollars, you created a billion dollars. Wealth is created. If Amazon stopped in 1998, it's not like the $2.5t Amazon is worth today would be distributed across Barnes and Noble, Pets.com and other retailers. Maybe some of it, but it's likely that the world would just be ~$2.5t poorer, likely more since AWS is the backbone of much of the online economy.