I am not sure, searching for "modern" reveals 27 hits and postmodern 14. Also, landmarks dominate the top 10 so i am not sure whether the poll more accuratly tracks the most liked building and not style. A style with more distributed votes would suffer (and, for example, there are more hits for postmodern than for art-deco).
Edit: By 'suffocate all others', I mean in an academic sense. Look at the designs produced by major architectural schools. They have been purged of older styles, just like the art world was purged of 'traditionally beautiful', confining it to art history.
This is a poll about americas favourite architecture and not in which style to build. I think the poll is largely a function of fame. Buildings are being build in all sorts of style, but I think the sobering result is that a style in itself is not really saving anyone. I also don't think style can only suffocate? A lot of cities are mixed in style.
Not according to https://en.wikipedia.org/wiki/America%27s_Favorite_Architect... - modernist buildings barely show up in that list. Of course you're right - beauty is subjective. So when a simple popularity poll fails to show support for their chosen style, architects resort to pseudo-intellectual justifications of why the people are wrong to dislike the featureless blocks of glass, steel and concrete built in their cities.