I didn't edit because the edited question would have still been a duplicate, but yes, context matters. This is mostly due to the difficulty in setting good boundaries on the scope of the site. Home theater and audiophile applications were clearly outside the realm of both AVP and Sound Design, so they were an easy definition. Additionally, while they may seem similar (and are in a few ways) there are also differences when dealing with professional audio devices and production PAs verses home audio gear.
In today's site, there is a good chance that the old questions might end up considered off topic as well (I'm not sure either way), but home theater is still off topic.
It is worth noting that we are not the only SE site with such a policy either. ServerFault, which is targeted at professional server and network administration, has a similar policy. If you know the professional context well enough to map your question to a professional context, you can still get an answer, but it will be answered in that professional context and it is possible some answers may not be applicable to you. If you specifically mention that it is for your home network, it is off topic though as the context is wrong.
The reasoning is the same, for a professional, asking how to configure a basic Linksys router isn't going to be a question, nor is trying to troubleshoot built in DHCP server issues. These are questions that aren't desired on a site primarily built to serve a professional community and so the professional boundary makes an easy to judge line, even if it may rule out some questions that would be ok in another context.
We don't really have a better way to try to subdivide it and prevent an overflow of non-professional questions that will make the site burdensome to the target audience, so we rely on context for making judgement calls. We have to be consistent with it so that when someone asks for home theater speaker recommendations, we can tell them it is off topic without them complaining that asking questions about how to wire up the home theater system wasn't off-topic. It just keeps chaining out without a hard line somewhere.