You can use "effective top tube" instead of "top tube."

Otherwise, most geometry characteristics haven't changed much. E.g. trail, wheelbase length, seat tube angles are basically the same.

The main differences won't be reflected in the numbers though. A frame with smaller triangles will be stiffer; frames and bikes in general are lighter than they were ~25 years ago; compacts might have 1 or even 2 fewer sizes than traditional frames. You can use geometry as a basic guide, and then do some test rides to see how it goes.