Ah, I did not quite get your comment - you are saying that _once they get to 40M (instead of 127M), they will have all those things - it will take a long time, though. Right now, Japan is famous for having very little open space and sky-high real-estate prices (and rents) - that's why I thought you were sarcastic.
I think the parent was saying they are on their way down to a population where open space would be more abundant and spacious housing would be more affordable, but they aren't there yet with their current population.
Can't say if you are being sarcastic or not?