Only child--“An only child would never learn to adjust

Only child--“An only child would never learn to adjust; an only child is likely to be spoilt. Any child needs company. There is nothing like a sibling”- there was a time many people used to feel this way. Times are changing and many families opt for an only child. . It is the personal decision of the couple .But do you agree with the veracity of the statements above? In our days, there was greater closeness among families, children of siblings used to get together . But even here, once we all grow up, there arises distances due to so many factors and constraints.This being the case, do the statements still hold water?