And what is wrong there? Our extension allows you to add any webpage to NotebookLM using our pop-up, which is clearly available on the screenshot. It's the reason for the permission, so your review doesn't make sense.
Edit: Again, YouTube is the main feature, and supporting other sites was requested by our users. If our approach does not fit your preferences, you are free to remove the extension. We have more than 400 000 users in browser stores who trust us and are happy to use our extension on a daily basis!