This could both be anti aliasing and the new high DPI support.
Anti aliasing makes the view look less pixelated but can also make it look fuzzy and is controlled from Windows > Preferences > OpenGl. I've so far used x16 myself because its the highest value I can have but I might lower it to get rid of some of the fuzzyness and better see line stipple.
The high DPI support allows everything in Sketchup (menus, toolbars, line widths, inference markers etc) to be upsized so you can see it more easily on a high res screen. To disable this I think you right click the SketchUp icon, open its properties and change some setting in the compatibility tab.