The problem with a statement like . . .you legitimize systemic inequalities, is how can you measure that result. Even if you could, If you want change you need to justify it within a framework that is congruent with reality, in order to create a theory that will resonate with people and change their mind. This means you must deal with the reality that some billionaires seem to legitimately do things for purely philanthropic reasons. However, that truth should be understood against the role of billionaires inside a system that results in deep and unfair inequalities. After all there are perhaps reasons why concentration of wealth in hands of a coordinated group be it a person Corp or government could potentially be beneficial, but the likelihood that they will use it for good is the critical factor. So that some do good proves nothing, unless we think random billionaires are going to use a given sum for a more beneficial purpose than the government (spoilers they won't).