The filter thing seems obviously true, but it doesn't rule out whole styles being better than others, even if the mediocre and pedestrian efforts from those styles were eventually winnowed out. Besides, each day people, somewhere, are making decisions about the next awful building. It doesn't seem enough to loftily let our descendents decide whether to pull down a building after we're all dead, before a single stone has been laid.

Consider this view as a thought experiment: say every Norman cathedral was beautiful. Maybe some were inspired and some were pedestrian, some were less beautiful because of the locally-available stone, some had long delays in construction and ended up with a mishmash of styles. Or whatever. You could filter them by appeal, or randomly, or any other method, and still end up with a bunch of beautiful buildings. Whereas it's not clear that any brutalist concrete cube will withstand the test of time. GIGO.