Watch for housing prices to come down over the next 50 years. The developed world just isn't having kids and even in the developing world the birthrates are falling. Give it another generation or two and there will be a surplus of housing.
Maybe ... but what we're seeing now is bigger and more expensive houses with fewer people in them. This raises the prices, because a couple with two incomes and no children can generally spend much more money on a house than a couple with one income and eight children can.
Fewer, later, and less-stable marriages also mean that more housing units have a single occupant, so the total number of units has to go up.