My guess is that stated support for the prototypical bad housing policies we love to hate would be pretty constant throughout the political spectrum (though that's just a guess). The issue is that that in BFN no one cares about rent control or constructing new buildings because housing is so cheap and space is so plentiful; only in places where housing is expensive and space is scarce do those issues get any political salience. And since those tend to be more liberal areas, we ascribe "liberal" to those policies as a descriptor.