Thank you for the feedback.
To answer to your points:
(1) It's Also the third link of the documentation, after Getting Started and How Let’s Encrypt Works
(2) It is indexed (but not well for particular questions)
(3) it is link in the first message of the forum Welcome to Let's Encrypt Community Support
I guess you are talking about the question template? If the person asking question is not technical, it helps to give a little help to formulate the problem. If the person doesn't give the answer to the question in the template, it's harder to help them.
I like the really visible blue top. Maybe it's more visible that the first pinned post.
I agree that it's painful,but I'm a little afraid that adding more text/explanation for that point will be confusing, the more text they have to read the less they will read. (and a moderator can always edit the post to add the missing formatting if it's too hard to read)
If you could write the blue top text, what would you put inside it ?
A mix of these three pinned posts?