[Kingofthehill]

The extensive streetcar (yellow and redcars) network was the precise reason why the city is as sprawled as it is today. You had redcars going all the way out to Redlands. With that said, it is worth mentioning that even during LA's pre-war heydey, transit ridership lagged behind comparable East Coast cities, the city embraced the automobile (and built the necessary infrastructure to accommodate it) before many other cities, and the bulk of LA's nabes were of the bungalow/cottage and duplex variety. Furthermore, LA's streetcars had long been in decline by the time suburbanization and white flight was in full effect.

While there are a few truly functionally urban nodes with significant multistory development (mainly in the triangle bounded by Downtown-Hollywood-Miracle Mile, which includes Koreatown, Westlake, and Pico-Union, among other nabes), such places were and are the exception, and not the norm. Curiously enough, alot of LA has densified following the dissolution of its streetcar system; Santa Monica, West Hollywood, Palms, Westwood/Brentwood, the lower Valley, and Mid-City sections, to make no mention of the adjacent South Bay, had thousands of dense, multifamily units (primarily in the form of Dingbats) created in the absence of mass transit.

Finally, I don't feel LA lacks an urban vibe at all. Perhaps if you are strictly speaking about aesthetics and build form, but LA's cultural offerings and amenities are the envy of many cities.