Copilot is a code completion, and authoring for developers.

It’s not a presenting a copy of trained material, rather generating new content based on what it has learned in the context of the problem / query discussed in the prompt.

Repositories available (complete copy) sounds more like a search engine cache, which is mentioned in the middle of the article (Bing).

So, is it Bing, the search engine or the AI model?

Perhaps I am missing the core here, but at the moment it seems like a Bing story dressed as AI story for traffic (arstechnica) and fame (lasso).