There has been A LOT of added functionality since Windows 3.1 days! Not just changes in the UI, but changes to security, API's, and so on. Windows, and for that matter other operating systems, are far more complex than they have ever been.
Possibly, but at least developers don't have to deal with the segmented memory model and other 16-bit limitations from Windows 3.1. Writing programs to run in the original 16-bit Windows API was one of the most byzantine things I have ever done.