Part of this is simply a function of the average age. There's a much bigger squeeze of life events when everyone dies at 60 instead of 90. We become older, meaning our life events are stretched out further, we leave school later, begin work later, buy a house later, have kids later, retire later, die later. Secondly, within the population the share of old is becoming bigger, meaning the average buyer is older, and also the average age of first buyers is older.
If you look through the statistics we are actually richer in terms of housing than ever before. There's two stats: home size, and persons-per-house. In the past half century or so, home size doubled while persons-per-house dropped by 25%. So we live in bigger homes and share them with fewer people, housing-per-person has been increasing decade after decade to the point it's almost 3x what it was since the war.
