Lagspike is correct, the macros existed in Vanilla, they just were more difficult to create at the time as you had to create a script or use an addon to do it(the scripting part) for you.
For example, Clique was offering all of that mouse-over functionality in 1.12 and only had to adjust its methods/frame calls when Blzizard shifted to secure frames and disabled certain scripting(in favor of the retail API) in TBC.