Are lung shots no longer considered to be good shots?
Funny how that appears to be the exact same zone shown in this oft-used image of where to shoot hogs, only this one has a heart shown as well. The purple here is a very good match for the red there, but this image is regularly used as a good image showing vitals.
Basically, I think all these pics (and there are some that are much worse) are garbage beyond showing approximate generalities. Most don't take take into account anything other than dead level broadside shots.
As for gut shooting, the red zone on the OP image won't result in that with a dead level broadside shot, not without hitting the lung(s) as well. If it is quartered toward you, then that may be another matter. Of course, I have managed to gut shoot hog where the shot entered at the neck. Shot placement, trajectory through the hog, and penetration will all come into play. Sure, the tip of the lung does overlap with the stomach, but so does the liver (good bleeder)and the spleen (good bleeder) overlaps with the stomach.
Most of the "guts" tend to be located from the most rearward ribs and back.
Three inches too high? The zone could be extended lower, but is corresponds with lung shooting fairly well.
Is it a perfect kill zone target? Nope. None really area, though. It just shows one area of shooting.
Somebody really needs to make an anatomically correct 3-D interactive see-through hog, deer, bear, etc. set of targets where hunters can see where shots are apt to go with various shot angles (assuming no major deflection). If you are in a tree stand shooting downward on a quartered hog, what would be the best shot placement? Quartered toward? Up hill? Etc. Nobody has done that yet, but it would be really cool.