oh i absolutely was in BLM land and Forest Service land all over Arizona, New Mexico, Texas and Oregon - with the right cell network service is fine in most places - just look at a coverage map - its pretty ubiquitous at this point.
I don’t trust coverage maps. Just driving around southern Indiana, something I do dozens of times a year, I regularly find large dead spots in cell coverage. I’m surprised it’s better in the much sparser west.