Hi all, this was posted as a new feature request back in 2024, and before that in 2022. It’s a feature we’d love to have because we see the same issues you do.
Our current fix has been to use custom CSS entered in the activity’s description WYSIWYG editor that hides the Take Course Button, and then create a new button in the Activity Instructions box with the preferred text. It’s not a quick fix by any means but it is functional and we can customize it to be different for unenrolled/enrolled/anonymous users.