All the engineering responses aside, there is something intangible about the feel of a good, well-balanced steel road frame. I can't really describe it, but I can feel it. I'm saddened by the fact that younger generations may never experience it for themselves. The little bit extra weight won't matter to most unless you have to climb in races with much lighter bikes.
The only analogy I can think of is the search for perfection with digital recording of any kind compared to traditional methods. It may be "perfect", but it's lifeless.