This is a very poor justification for a very bad in-game system.
Making players wait for hours and hours to get an empty plot of land, is frankly not the same as a mount. At all. In any conceivable way.
Mounts are tools, and everyone can get a chocobo very early into the game. It may not look as fancy, and people can aspire to collect more, but they have the *functionality* of being able to
get around the game quickly. Imagine having to wait outside of plots rolling randomly to get your first mount, spending potentially dozens of hours clicking a sign just so it won't take as long to get around.
That's the situation right now with player housing.