Yes. Like they did with the githubsearch for users that are not logged in.
At first, they brought it back. Then they changed to limits so you get between zero and two searches before getting an error message that you have hit some kind of limit.
Instead of polluting PRs, Copilot will insert comments and logging and text fields and buttons with links to web sites with helpful product tips into your code and user interfaces.
I mean, this is a very obvious future step. I was imagining this too, although I stopped short at the 'ads in comments' stage, but who knows, they could easily go further.
Migrating away from Github just increased in priority.