However, I personally would worry about a tool like this being a little heavy handed on the ignoring, leading to missing topics that you might actually care about just because some buzzwords were thrown around in the discussion.
You are the one who will be putting certain discussions on ignore, so do it properly. Check what the thread is about, and if you absolutely hate it, remove it from your field of vision. It shouldn't be an automatic thing that relies on keyword filtering because there would be too many issues with it.