I don't think this is a complete characterization of what happened. From looking at a previous thread (https://news.ycombinator.com/item?id=39369353), the owner curiously did not allow outside contributions to his GPL project. This is odd, especially if it seems like he was complaining about having issues with maintenance of the project. Then, after he tried to switch the license, he deleted/obfuscated the repo history. Even though it is GPL, because he had the "foresight" of not allowing outside contributions, he was able to take this action unilaterally. I suspect that the owner had his mind on commercialization from the very beginning, and was using the whole FOSS bit as a way to get free publicity before rugpulling.