You are comparing apple to orange.
Yes, US have lower population density than China.
But that have disadvantages too.
When you are american living in suburbs and have office in downtown, it will be a nightmare.
US suburbs much less developed than Chinese suburbs.
So you need to depends on your own car, and wasting hours of time everyday in slow but serious traffic jam
What a suck life.
Meanwhile in China, if you live in subrubs and have office in downtown. You can take subway or other public transportation easily, and 30 minutes later you already in your bathub, relaxing in warm water.
US suburbs are more like Chinese small town, if you want to compare.
Just look at this, you can see small towns across China