Billionaireness is profoundly extractive by definition. Leave class out of it and billionaires inherently benefit themselves against any and every system they are in, and that's including other billionaires (they're exceedingly competitive).

That means that billionaires also act against the interests of the donor class as a matter of course. If they were not the very definition of unaccountable power, you wouldn't see anybody defending them or their typical behaviors.