Homelessness, poor physical or mental health, crime, domestic violence, discrimination. There's a long list of social ills that get worse when a society is inequitable and unequal. These problems and their effects go down significantly when a society acts to maintain its own health and distribution of resources is more equal, there is social mobility, individuals are under less financial stress, etc... Number will never go to zero or even close but there are countries where the base homelessness rate is similar to the US but the manifestation of problem is very different as is the approach, mostly that being homeless isn't considered criminal. e.g. very few people sleep rough, their homelessness period is shorter and living in cars is not normal.
Just that last fact, that living in cars is relatively common and that includes children, makes me look at the US and decide that yes, US society is broken.