Nobody in big cities knows their neighbors. And very few people organize against poverty, against their bosses, landlords, and police abuse. They could have a good life if they did, but don't underestimate the capacity of an oppressive system to isolate people (because it's the only way it can survive).
You can have lots of housing, cheap housing, and quality housing, but never really all three. Vienna, which a lot of people like bringing up as an example of a friendly masss housing program, recorded flat or declining population every decade until 2000, and has still not recovered from its pre-WWI peak, which wasn't even very big at 2M people.
People respect the rules (otherwise they face consequences for asocial behaviour) and this makes the city function like a well oiled machine.
The same scheme wouldn't work in many Western cities, too many self-absorbed people thinking they're more important than their community.
If people in Singapore are more community minded, then why the need for the harsh enforcement? (You know, public whippings for putting your shoes on the wrong feet or whatever...)