This has been discussed and answered so many times on the forum.
It surely is a planned and desirable feature, but it's quite complex because, opposite to other pushback solutions, GSX doesn't use the default MSFS Pushback, which is a dumb Left/Right/Straight system driven by key events so, it's enough to set a negative speed and it will pull instead of push.
GSX pushback is completely custom, and it's main different is that is able to figure out a pushback automatically without any user intervention, and it supports the way more complex inverse kinematic of possibly using a toolbar, and all this calculations should change when pulling.
In addition to that, since GSX pushback is fully customizable, the editor should be also changed to allow to indicate which segments should be done in reverse, and that should ideally be possible without breaking compatibility with the myriad of existing GSX custom Profiles.