I use a 43" 4K monitor as my main monitor and a 27" 1440p in portrait as my secondary. I typically have the Unity editor on my main monitor though and C# code on the secondary and in that arrangement with the font at a size I find comfortable I still need to wrap at around 120 columns. The other arrangement I sometimes use is two side by side windows on the 4K monitor and even that still has a width limit.
C# is pretty bad in this regard compared to C++ because the standard formatting rules of indenting namespaces and the fact that there are no free functions wastes a lot of the left hand side most of the time.
