As this is a Software Recommendations site, I doubt there will be many (if any at all) questions that will be on-topic talking about mac hardware.
So I propose we show users who try to use the mac tag the following message:
The tag [mac] refers to the hardware of an Apple computer. This is a software recommendations site, so if you are looking for a recommendation on OSX software (the OS that runs on Mac's, please use the [tag:osx] tag.
Unless I'm mistaken and there genuinely are questions that would be on topic on this site about the mac hardware.