The best answer I've seen to this question is https://www.murilopereira.com/the-values-of-emacs-the-neovim...
Amongst other things, it lists different values that each tool prioritizes, and how "Core values are self-reinforcing. They attract like-minded people, who will then defend them."
Emacs: Extensibility, Freedom, Introspectability, Keyboard centrism, Stability, Text centrism.
VSCode: Approachability, Integration, Maintainability, Progressiveness, Velocity.
That is, even if VS Code achieves technical parity with Emacs (wrt introspectibility/extensibility), its community might not prioritize using VS Code for things beyond editing code.
Or maybe it will. These things are difficult to predict!