We can quantify the impact of the scripting tools pretty easily - 1.5k requests per day! I just went on Reddit and viewed a few posts, and it caused about 500 HTTP requests in DevTools. Luckily HN is not that bloated, but I just don't see the number of requests as meaningful even if it was orders of magnitude higher.
As the OP said, they don't do anything when the server isn't vulnerable, and serving a 404 page is incredibly cheap.
As the OP said, they don't do anything when the server isn't vulnerable, and serving a 404 page is incredibly cheap.