The passage you quoted from his letter is the reason I qualified my comparison to Roark with "might." I give him a pass on his false contrasting of nobility with selfishness, however, in consideration of the larger point he is making, that it's fine to focus on your education without embroiling yourself in political disputes that do not materially concern you, i.e. to act in your rational self-interest. In addition, one must consider that these are Berkeley students he is addressing, the majority of whom are probably altruists. His message would be less pragmatically effective if framed in egoistic terms.
Would you not agree that Coward is at least similar to Roark in that he is a uniquely talented maverick in his profession whose innovative and superior work threatens colleagues who have an entrenched interest in maintaining the status quo, resulting in their persecution of him?