Let's say we pick spots in the desert to store all our trash. How we do we move all the trash from the population centers to the landfill? Fleets of trucks and railcars which emit tons of CO2 and would be better used elsewhere in the economy.

If we place landfills closer to population centers, then there is a much high opportunity cost for more productive uses for that land and greater care required for preparing the landfill so that contaminants don't leak into the water supply.

Either way, it would be better to reduce landfill space as much as possible.

More philosophically, we can't just keep living this "throw away lifestyle". There is a finite amount of land and resources. My generation is growing up facing a total climate collapse, and this way of thinking is the major reason why.