What changed a lot is occupancy. It used to be that homes were multi-generational and families were larger. I don’t know in this context, but in Europe until recently, it was common for grandparents-parents-kids to live all together, with sibling of the parents often included and potentially their families too. An apartment occupancy rate around 5-7 was common, while single family homes where unheard of until last century. This strengthened social ties, smoothly provided care for who needed it, and made the family more economically resilient.