Yes, there is obviously a lot of space on the planet, but we should talk about places people actually and increasingly live, ie. Asian cities, particularly Chinese and Indian cities.
So let's rephrase that to "At current densities where most of the world's people actually live there is no way everyone can have a garden, because of lack of space."
So let's rephrase that to "At current densities where most of the world's people actually live there is no way everyone can have a garden, because of lack of space."