In a way, I don't think it's possible to specify a "site-policy" about this. It is up to each user to post comments as they wish, and up to each user to improve their comments as they wish.
This one comes directly from a collection of Frequently Posted Comments for users of the Auto-Comments scriptAuto-Comments script, as such it is several users that already uses the comment. But there's also a whole bunch of users that do not uses this as a frequently posted comment, or uses another variation of this.
Now onto the discussion itself:
By showing this to the new user, they could get in the habit of posting titles that, while they are interesting, they do not always tell a lot about the code or the post itself.
This feels to me like a "What if..." scenario. Is it a problem today with interesting but not entirely accurate titles? In my opinion, no.
The "Best of CR titles" post(s) are meant for inspiration, and I find that many of them are relevant to what the code does.
The titles that the comment primarily want to avoid are titles like "How can I simplify this code?" or "Coding practice in Java". Compared to these, I find the ones provided in the "Best of Code Review" posts a lot better.
The auto-comment is related to How to get the best value out of Code Review - Asking Questions - Title, but is intended to provide a suggestion that fits in a comment
Can the comment be improved? Always.
Will the comment ever be perfect? Never.
Also remember that comments are "second-class citizens" on Stack Exchange sites.
