People who don't grow up with close family or friends may lose the ability to relate to others. They don't know how to communicate or connect. They are less likely to develop emotional and social resilience.
Although we know about shy children or adults or those with social difficulties, many people are losing the art of saying what they think, feel and want without alienating, stressing or abusing others.
After World War 2 the nuclear family took over. Even this has been eroded by divorce, remarriage, unusual working hours, the need for family chauffeuring, television meals, takeaway food etc.
The result is that at school, home or the workplace poor communication skills are handicapping people's interactions with others.