'"We" is society at large.'
Society at large has decided that it likes suburbs and McMansions just fine. You don't get to make that decision for other people, just because you use the word "we".
'And half the point of this article is that "young Americans" cannot afford those country homes with long commutes'
Well, then, that's the problem needs to be solved, rather than patching it by forcing people back into the crowded urban environments that they so obviously do not want to live in.
'denser Urban living since modern transportation in the form of personal automobiles is also incredibly expensive.'
1) Why does it need to be dense and urban?
2) No, they aren't. In 1950 a median-priced new car cost about $1,500, somewhat more than half the median annual wage. Today you can get a new Ford Focus for about $17,000, which is... somewhat more than half the $32,140 median annual wage for those over 25.
Also, most families in 1950 had one car, period. Most families now have at least two. That doesn't tend to support your claim that cars have gotten more expensive.