No one is saying that architecture should remain stagnant or not progress what we are supporting (and my wife is an architect by the way) is the preservation of what is already there and is considered a city landmark. Progress is fine and a reality of life much like any other evolutionary process but often times just like biology it mutates into shear ugliness.
Case and point the new De Young, the Embarcadero Fountain,or God forbid the monstrosity that replaced the beloved Fox Theater.
The problem is that this architecture is monloithic expensive and is impossible to remove once placed. It is a failed experiment that becomes a public eyesore.
Some architectural evolutions are wonderful and some modern architecture is impressive but I think few will argue with me that the above referenced architectural "marvels" or the famed "bankers heart" have no aesthetic value whatsoever, just more failed experiments that we have to live with( and often times pay for)