I don't think it's all billionaires. Just this one.
It is a warning to all of them; we will never see an independent even get through the primaries again, never mind the general election. This has been developed since the day after the 2016 election; the Republocrat club will never host an outsider they don’t control. Americans have just seen the last President who gave a hoot about the average American citizen.
It's any billionaire. Not even Jeff Bezos can outspend the government if it puts him in its sights.