To be clear, I've no issue in general with low density homes (some people do), I live in one, so I would be a hypocrite if I opposed them. What I am opposed to is building acre after acre of suburbia with the only way out to drive a car. That's objectively bad. It's bad for air pollution, it's bad for people's health ("the exercise of life" - walking to the shops or to the metro-station is good for your health), and it's generally unsustainable because these areas cost too much to maintain for the property tax paid. When I looked at the house to buy, I chose somewhere that was close to the town centre. This morning, I walked back from dropping off my car to have it serviced. It was a 15 minute walk. I'd have had to get a cab, or wait around, if it was one of those American stroads covered back to back in Wal-Mart's and Quick-Tyre-Fitting-Co's.
We should be building more transport-oriented development. It was like my example from some time ago, comparing an older 1930's Toronto suburb to modern Colorado. Take a good inner city suburb that's located near amenities and a metro station, build detached, semi-detached terraced homes and flats there, with the flats generally being built closer to the metro. The properties will be naturally a little closer together, but would still be pretty decent in terms of internal space; it might be more common to build a two-storey property instead of a one-storey to maximise land usage though. But ultimately, that should be the goal. Unfortunately, in many areas, it's literally illegal to build this type of mixed-use area, because commercial properties (of any kind) can't be zoned in the same area as residential, even if those commercial properties are servicing the residents. And it's illegal to mix single family homes with higher density flats, despite the two being absolutely compatible. It's absolutely bonkers city planning.