This is a common feature of notable critics, probably because it is far easier to criticize than to solve problems. It's far easier to point out why the suburbs suck than to design and advocate effectively for alternatives that address the same needs that the suburbs try to address.
BTW I think your critique is actually deeper than Kunstler's in that it gets to the totalitarian underpinnings of this type of high modernism. People seem to mistakenly associate high modernism with the enlightenment when it's more of a return to pre-enlightenment authoritarianism.
High modernism is a secular materialist version of divine right of kings, with baroque religious theories replaced with opulent displays of indifferent wealth and with sterility replacing aesthetic grandeur as a display of power. The latter may be because aesthetic indifference serves today as a more effective display of power than baroque over-done aesthetics with gold leaf and curlicues.
I recall him in 2012 saying that the aviation industry would be history by 2018... that clearly didnt pan out. The theory was reasonable but the time frame was wildly out of whack.