The prejudice is based on billionaires being the first to get access to the cure for aging in these hypothetical scenarios.

While everyone else can't afford it. Hard to think of a more demoralizing "off with their heads" dystopian scenario.

Think of rich people as beta testers.

On a personal level it would be demoralizing to see some billionaires live multiple lifetimes, but only a tad more demoralizing than seeing the wealth disparity we already have and the changing line of idiot faces at the top.

Well, sure, but there are solutions to those particular billionaires. We don't have any politicians I'm aware of that are willing to consider those solutions, but they exist. Societies, including the US (to some degree), have solved the problem of oligarchs in the past through various means. We can do it again, and should consider all the options.

especially given how they fund their billions from 401k through rapid inclusion into indexes, building DCs near residential areas, stealing IP, regulatory capture and hype driving manipulations.