I'm not sure if this is the place to talk about the specific content of the security standards or if the SSG is more "meta"...

I see there is a test Rule ID: package_aide_installed. I am inclined to think that the spirit of this test is to have a file integrity monitoring (FIM) system. But why AIDE specifically? There are a few options for FIM, but not too many that one couldn't write tests to ensure that at least one of the handful of fully featured OSS FIM solutions is installed and configured. (other options that come to mind are OSSEC and Samhain) Additionally, AIDE development seems to be stagnant and perhaps not the best choice at this time.

Where is this guidance coming from? Is the source of the guidance really technology specific or is the choice of AIDE just a specific interpretation of a more general guidance for a FIM solution? What's the rationale, if so?