Yeah, I see the point. My only good argument against trying to optimize relative outcomes is that it isn't practical to try to do so.
To talk about the difficulties of implementing true socialism would be beating a dead horse, I think. But even if we could remove wealth inequality completely, people would still find ways to feel better or worse than others (sports, looks, social skills, intelligence, etc.). My high school in the suburbs was fairly homogenous from a socioeconomic standpoint, but that microcosm seemed more hierarchical than any other point in life.
I also would expect the good-or-bad feelings people get by making comparisons are more-or-less ordinal in nature, so I think people would manage to feel just as bad about small wealth differences (keeping up with the Jones's) if there were no more billionaires.
I admit it's a difficult thing to measure and to discuss, but I also do think that the tide is rising, but being creatures who's feel good brain chemicals are related to relative outcomes (see the primates w/ cucumber vs grapes studies), we're also feeling a bad feeling because we see others doing better to a greater extent than we are...