Under the narrow definition of garbage provided (household waste), and using the system of imaginary points (what is cheaper instead of what costs our environment more), then sure that's the conclusion the OP came up with. After endless fables and allegories and precious little actual numbers.
The idea that we cut thousands of acres of wood a year to make paper, yet somehow the garbage will fit in a smaller space is on the surface preposterous.
That landfills are any kind of solution is also very debatable. They poison the area around for generations. My local town, very PC and very educated, has a massive landfill groundwater plume that destroys wells and makes soil toxic for 20 miles 'downwind'. Did we do it wrong? Who does it right?
You've heard about the 'plastic continent' circling in the ocean, made of a soup of plastic waste that's never going to go away? Do we count those thousands of square miles in the 'landfill equation'?
We have endless space, sure, as long as we're willing to consume it in those ways. Ecology to burn! We'll never need it, surely. Certainly we won't miss it, its outside of town and nobody goes there.