The IntelliCode and Copilot teams have been collaborating closely together, since we want them to provide a "better together" experience. However, the underlying tech isn't the same. Copilot is powered by OpenAI Codex, and enables rich code synthesis via a cloud service. Whereas IntelliCode uses multiple local models, to enhance various parts of the editor (e.g. prioritizing the completion list based on your context, detecting "repeated edits" and suggesting additional refactorings).
https://visualstudio.microsoft.com/services/intellicode/
I bet it's the same people, trying to push their crap into all sorts of successful products.