Well, obviously it's not a be-all, end-all system. But the vast majority of threads created lately are worthless and redundant, so it's not like we run the risk of impoverishing the forum contents, quite the opposite.

However, this approach has one overwhelming merit : it's doable (if Reggie decides so), and automatic. All other suggestions rely on volunteer manpower, time & effort (refactoring forum information to the Wiki, moderators merging and closing threads etc. ). They have been suggested many times before and have consistently failed to materialize. I predict they will continue to fail, especially with the current mess.

Moreover, these approaches are not mutually exclusive but complementary : if some authoritarian software throttle like the one I mentioned (or another such) could take care of say 80% of the problem, then a core of dedicated moderators and redactors would stand a chance of coping with the rest.