Nelson....
"figfan/James", and a few others have said that chopping the original trunk was the quick route to growing Ficus carica as a bonsai. They are right, and fig leaves will never reduce to be in scale with the size of the trees. Older trees are usually treated to a "trunk chop" and a new rack of branches are grown and selected where needed. Most large diameter, deciduous bonsai are grown this way, in training beds, until the tree is developed to the point where it can be displayed in the proper pots. It's all illusion. All the hard work and the years of training these plants is usually never seen by admirers. What the general public sees is the final, finished product on display, at shows. It's possible to get these trees to set fruit, but they are not grown for the figs, but the shape, and the illusion of gnarly age.
Most of the posted photos show plants that have had multiple trunk-chops. That's how the abrupt changes in the direction of the branches have been created. It is a fascinating process, and most bonsai are works in progress, but fairly easy with figs because they are so dynamic, and put out plenty of new wood that can be trained. Try it on an old "Brown Turkey" or trees that have plenty of bottom branches. Think outside the box, and "create" a twisted, contorted fig tree of your own. Standard growing practices still apply, even if a fig tree has been given the bonsai treatment.
Good luck. Show us some before and after photos.
Frank