If you’re in the desert just about anything works, but if there’s no chance of bad weather it’s nice to be able to skip the rain fly. If the area doesn’t have much for wind a design with two poles is super simple to put up.
There are probably 50 three-season dome tents like this that weight about 5 lbs and are about $200. More expensive three-season tents are either made with lighter materials to save weight or more durable designs and fabric to hold up in bad weather.
Maybe it’s just me, but the wear and tear of camping on rocks, gravel and sand, combined with occasional high winds that can flatten or blow away an unoccupied tent like a tumbleweed, kept me away from the more expensive extra light tents.
This REI tent is very similar to one I spent over 100 nights in.