Not really making an argument so much as trying to understand what Austin is trying to accomplish with its complete lack of direction downtown. I don't hate condos, I owned and lived in them. I wouldn't buy one in Austin if they were giving them away. It is not a pleasant place to live for the demographic you just described.
Downtown Austin is simply nowhere in the same stratosphere as any of those neighborhoods in terms of a functionally livable environment. I have actually lived in River North, the Financial District, and downtown Austin (albeit well before the boom). Austin doesn't just lag behind these other locations, it's not even reasonable to compare them. Pied-à-terres are not the issue, as we clearly have way more than anyone wants to inhabit. The issue is what surrounds them, and while not a complete dead zone it's damn close. I don't know who we're trying to attract to downtown, but it isn't exactly filled with DINKs, affluent singles, or downsizing empty nesters. There's a reason. And those neighborhoods you mention did not start to revitalize by building condos and nothing else. If I have a point at all, that's it. We're doing it backward and I'm trying to understand why. It's not working.
My concern is I don't think we're moving forward. We have a bunch of dwellings with no one living in them full time, like a Chinese suburban development.