It appears that there are two schools of thought here:

1. If a question is relevant to systems/network administration, it is on topic, even if it is also a generic question about a particular platform or technology.

2. If a question is relevant to systems/network administration, but it is also relevant to computing in general, it should be closed and/or migrated to SuperUser and/or a platform-specific StackExchange site.

In practice, the ServerFault community seems to favor option #2. Questions that are relevant to systems/network administration, but are also relevant to personal computing, tend to get closed or migrated.

Is this by design?