All of the posts on here are a part of a vast database. There are search and sort functions that will allow a user to do, more or less, what you are asking. The process of organizing posts into useful groupings ultimately must fall somewhat on the users.
There are two sides to this coin:
Regarding gear reviews, someone who wished to solicit a review should make sure the thread title is something like "Sage XPS, 3 weight and above" rather than "Need opinions on a rod."
Anyone posting an unsolicited review could use a title such as "Sage XPS Review," or "Review: Sage XPS, St. Croix Avid and Orvis Zero Gravity," or just "Sage."
The second side of the coin is the person seeking a review. They would use the search and sort functions to find all posts with "Sage XPS" in the title or appearing anywhere in the post. This would result in a sorting of the entire database to extract only those posts where the searched item is mentioned.
A specific "Review" forum, in my opinion, would encourage review spamming and advertisements in the guise of reviews. I would suspect we would see a proliferation of gear reviews from new users.
In the past, people looking for opinions on specific gear items have used the Gear Forum and simply asked about the item they were researching. The process seems to have worked so far. I advise everyone to become familiar with the search and sort functions. It is a very helpful feature that allows users to "customize" their viewing of posts to their particular tastes.