I struggled initially to understand what this was about. Then, after digging a little bit more, I see that it is an open and rich environment to visualize (while executing) data from different perspectives while being extensible from within the same environment (using Pharo), allowing to create a rich and custom ecosystem for data and systems exploration in an orderly and structured manner.

What I couldn't find is information about workshops or forums besides discord to talk and understand about its possibilities.

Specifically, I had trouble understanding how to apply it to other programming languages and their frameworks. I can see that for some of them (e.g. PHP) you have to export the project with a tool and then import it into GToolkit, but that converts such a system into just an static structure to be analyzed, but not a live system to experiment with. This would mean that live documentation would require permanently exporting and then importing the code from such system. To get a living system + its real time perspectives and embedded live documentation it seems you must program the system in Pharo.