People are quick to blame the housing area design as the cause of not being able to purchase a personal house.

However housing originally was designed as a FC feature. They opened the housing later for personal use due to large amounts of residential areas being sparsely populated or empty because at the time buying a house was a huge thing even for an FC. Though I think part of it was most wanted the large or medium plots. When it was opened for personal use the small plots all disappeared rather quickly.

As it is now I don't think its too much about the playerbase size increase. Its an increase of players that know how to actually make gil in this game and as such can actually afford a house paired with a lack of cash sinks that players can spend gil on reducing the amount of gil in circulation.