The generation that lived through that, the next generation does not wish to live through it, as alternatives are "available" now (at least on paper). Those kids who grew up in 50m2 with no privacy, and at the same time absorbed western TV, where 300m2 detached house is a base in every show - formed their dreams towards that. This is why everyone is delaying family, because the image in their head is that to be truly happy, this is what you need. Very few people, living in those tight conditions grew up to be happy about their childhood.