I think architecture is more than just art, and what Roark is after is more than just the form. He also emphasizes on he can make his buildings with more efficient use of space, which is why I think it is appropriate that Rand uses architecture as an medium to express her ideals. In other words, I think what I am trying to emphasize is that Roark's ideals will in fact advance and impact human civilization because his ideals are more than just self-expression. Architecture in Roark's case is the making of space, spaces that can radically change people's way of living. The building he burned down was a model of low-income housing, which would impact the fundamentals of human society and economics. Comfortable office buildings can increase productivity, sustainable buildings can decrease energy consumption. Buildings in fact impact human lives more than people realize.

Steve Jobs came to my mind as well. Maybe Roark is more widely derided because the book/readers focus a lot on his character while people focus more on Steve Jobs' achievements?