>>44224450>It's not like single people are moving into a single family suburban home by themselvesIt's about the economics of pure square footage. Two units for one person each with all the fixed costs associated with planning and zoning (humanity's greatest sin) requires more space per capita than if those two units were shared. Even without planning and zoning space gets reused and shared when multiple people live together. This brings the cost per square foot up over time and brings up cost.
And yeah, people are living with their parents than ever, second highest time was the great depression.