So the desktop view is built to be highly responsive, adjusting to fit various width screens. Desktop view is meant to work on an ultra-widescreen high resolution desktop monitor as well as on an older, square, low resolution monitor or a 10" tablet. Desktop view will continue to adjust down to smaller screens, like phones, but not everything works (as you noticed), which is where mobile view comes in.
99+% of the time users on a phone get mobile view, and all is well. Something strange happened with your phone and you ended up in desktop view.