I agree, that’s why it just gives simple suggestions to users.
one use-case can be for blog posts. from technical point of view, It can help the SEO of forums. from the UX point of view, it can really help forums to have better structured posts which can be read easier.
lots of users write the way they used to in forums (just like a chat software), while they can be educated to write better and in a more readable style.
Also it can be a setting for the admins to turn it on or off.