Every time they mass-build housing, the results are horrible. The quality of the homes is always "transitional". In Europe or even New York, you can rent flats which are large enough for a family and constructed to give you a sense of privacy, even with density. Floors and ceilings and walls are solid enough you barely notice you're sharing the building. Shops are always close by, as well as public transport and schools. California high-occupancy buildings are always in the middle of nowhere, made on the cheap, meant to last years - not decades - and aimed at single 20 somethings without any thought to the long term or general community. If you can't buy a bottle of milk and some bread without getting into a car, you're doing it wrong.
I grew up in and around Boston, where three family homes and corner groceries were the norm, schools were in the neighborhood and the T could get you just about anywhere. I remember seeing Karate Kid when I was young and boggled at the apartment he lived in (with the empty pool and all the doors facing in like a motel) and couldn't imagine that was a real apartment building, but even 30 years later, they're still everywhere in California, and newer versions aren't much better. Apartments are for collecting poor people and built as such, and suburbia everywhere else.