Let's start with the basics, if you regularly juggle between a Windows PC and a Mac, then the ability to be able to sync your interaction history is certainly beneficial. Note also that the same applies if you wish to resume a conversation initiated on your smartphone app.
ChatGPT also benefits from exclusive features reserved for subscribers who do not find their place within Microsoft Copilot. This is for example the case of the o1 model, whose ceilings have recently been extended, as well as Canvas mode.
Indeed, for OpenAI, it is above all a question of opening up to a new base of potential customers, by encouraging them to migrate to a paid offer which will unlock several interesting features. So, if you have a paid subscription, then perhaps you have also created your personalized GPTs (or Custom GPT), these bots meeting specific needs to perform certain tasks or answer questions more precisely.
Also, we can wonder if, like macOS, OpenAI intends to allow ChatGPT some interactions with third-party Windows software. In this case, the sculpin could overshadow the Copilot+ PCs a little. Incidentally, initial work is moving in this direction and the chatbot recently appeared in the experimental version of Powershell. The integration of AI within the terminal then offers a tool capable of assisting system administrators in the automation and management of their tasks.