Thanks for the kind words.
In regard to your question, if it is a stub, then you can safely remove it and replace it with the correct content relevant to the article’s subject.
Whenever you are working on a file that someone else is working on, if you both edit the same locations, there will be a merge conflict when both of your branches (features) will be reviewed in a pull request. That is why it is important to edit files (if it is possible) at their end.
Commenting out code is discouraged since when you open your pull request, the reviewer will see the changes you have made (and see the previous state), so it will still be visible. If everything in your revision is satisfactory, there will be no need to keep the commented code there.
Hope that helps and happy coding.