The idea being that institutions like property and legacies such as industrial or commercial giants are worth huge sacrifices, including the lives of others. I kind of see Nietzsche's version of the Ubermensch being those individuals. I agree with you that the inbred, inheritors of wealth are not admirable on their merits or personal achievements but Nietzsche I dont believe was thinking that way because someone could be personally brilliant but not change the world.
Its the great man theory of history versus the industrial or materialistic theory. I think both theories of history are only partially correct. Although when I think about it my familiarity with The Geneology of Morals or AntiChrist mean that the idea that the strong protect the weak would be totally anathema to Nietzsche, that's like what he attacked as a slave religion.
In terms of equality, I think that people are different in terms of talents, they do develop different but I'm not sure that the rewards that flow to them should necessarily be dictated by their merits, I dont believe the world is a meritocracy but even if it where its not reason to suppose that those who are ugly, unpopular, untalented etc. should perish simply because they are that way. Most anti-egalitarian theorising at one point or another has to address that one and a lot of the time its a philosophical blind spot, they prefer to think about the just desserts benefit those who are most deserving without giving a thought to how that's decided and then what happens to the "others" and losers.