Yeah, no idea where they came up with the info on the coupe vs cab values, but cabs have ALWAYS had higher market values than the coupes, and I can't think of any phenomenon in the car market which would cause a sudden reversal of that . And that's not just for 968s, but pretty much true when it comes to any make and model. The fact that coupes are a " better " car does not necessarily affect its market desirability vs the cab.
As for the lines, everyone here is probably very aware that I am a die-hard coupe fan and would never drive a cab, but I do think on the 968 , the cab's lines are a bit nicer , for one reason : the coupe's hatchback does make the car look slightly more "dated", in spite of a significant number of prestige cars ( even Ferrari ) having produced cars with medium to large hatch-back styles in this current decade .
Last, if you have a 968 in " excellent " condition and sell it even for the highest price point on that Hagerty scale, you're selling yourself short ! This car has a far greater value to you than the $ 20 or even $ 30 k you might get for it . Unless you really need the money, which is another matter . I'd argue that you'll only start to find other truly comparable cars once to hit above the $ 45 K threshold ..