How does the extrude of a freestyle differs from that of GSD in catia?
Once generated the surface from a sketch with Extrude Surface in Free Style Workbench it can not be changed because this surface is created as an isolated element and this command create a different surface for each part of the sketch , don't keep link with any related build element, when you select it you don't have any option to change, you can change the sketch but it will not reflect at the created surfaces. But, when you create a surface from sketch with Extrude Surface in GSD workbench, it is a unique changeable surface by the parametric interface, you just click or select the surface and you will be able to access the Extruded Surface Definition windows and change the profile, the extrusion limits , type and dimensions as well make a mirror option or reverse the direction.
Now you probably are question why Dassault Systèmes did a command like it and I will tell you to get a number of surface isolated and independent using a Extrude Surface from GSD workbench you will need split the result with the command Disassemble expending more time and memory
Hope it help you