Yeah the imperfection is no excuse. But when the forum gives you out of the ball park answer, what else can you do? Lol.Let's not forget that this, in and of itself, is another big reason posts are "ignored". 24 hours is a very short window to ensure an answer to a question, 48 hours not so much. As Renegade said, it's all about patience. If a post isn't answered in 24 hours, wait 48; if it isn't answer in 48, wait 72; if after three days it still hasn't been answered, THEN it's being ignored. Usually, posts are answered in just a couple hours. That said, to just expect an answer in less than 24 hours is ridiculous.
In fact, I don't think we even have a rule for old threads. Most other boards do, I don't think we do. For somebody to necro an old thread is always preferable to somebody creating a new one for a subject that already exists. It's the actual bumping itself which is against the rules.
EDIT: As for your quips with the search function, it isn't as bad as you make it out. While it is a bit more difficult to locate a specific thread from several months (or years) ago, that isn't where the issue is; members who ask questions that were already answered eons ago aren't gonna get hounded. The issue is when a member asks a question that could be answered with a quick search (emphasis on the "quick"). I facepalm every time somebody asks for a Skyrim save when simply searching "skyrim" brings up five on the first page; when somebody asks for the Dragon's Dogma editor when simply searching "dogma" brings it up on the first page; when somebody asks how to mod Halo 4 when simply searching "halo" brings it up on the first page.
The search tool isn't perfect, but that imperfection is no excuse to not at least try to use it. In understandable circumstances such as what you describe, nobody is going to get toes stepped on. But any time the search feature is suggested as the answer to a question, it's because the person obviously didn't try.