Sublime 3, Windows 10, Resolution 2560x1440
Wrap_Width set to 180, single layout
My sample line is 160 chars wide and displays fine as expected. The moment I enter distraction-free mode, the line gets wrapped at column 118.
There is ample unused space to the left (almost 1/3 of the entire screen) - so no space based need for this rather unexpected behaviour; I would consider this a bug…