> They are the least full of life of usual ecosystems, so if you want to minimize harm when building large infrastructure, they're the logical place to put the infrastructure.

I don't think that necessarily follows — desert ecosystems are often relatively fragile. Small changes to conditions can have a disproportionate, negative effect on the plants and animals that live there. (Or a positive effect on some species, which often means a negative effect on others — i.e. things thrown out of balance.)