There are dozens of Stack Exchange sites. Server Fault is just one of them. Each site has a FAQ explaining the purpose of the site's existence. No site here is without a specific purpose.
Each site has a target audience and content matter; some are more specific than others. Server Fault is squarely aimed at System Administrators (and related support staff) and topics which include problems they may face while conducting that job (not one or the other; both).
If you want to propose a new site, Area 51 is a SE site exclusively for proposing new SE sites.