While the current comment feedback placeholder is good for an individual article, it isn't optimal if you want an identical placeholder text for every article in your world every time.
The idea for the feature is that under World Configuration > Display > Global Content, you have an extra box for global comment feedback placeholder. Whatever is put there will be put in every article's comment placeholder.
The only exception would be articles whose feedback placeholder is already filled in on an individual level. There, the global placeholder is overwritten by the one of the article itself.
The main benefit of this feature would be mostly convenience and consistency for worldbuilders. Users can then edit the placeholders from a single source and have them apply to all articles at once without the hassle of copy-pasting the same text article by article.