For a new person, that's not the first thing they're thinking about. It's probably not really what they're thinking about at all, in some cases, e.g. someone just diagnosed with diabetes. But people do want answers and follow-through.

Moreover, if someone is generally posting an original topic, they want to see responses. Email notifications, in the situation where someone posts an original piece of content, is not really an intrusive feature because people want follow-up. In fact, it's a standard on a platform like Facebook, where almost *any* action taken defaults you into receiving updates to that thread/area of content. Not saying that should be a standard for us/anyone, but there are certainly positive elements that can be gleaned.

I think that allowing communities to take a controlled, precise and specific approach to auto-subscription is reasonable.