My answer is admittedly too long (as most of my answers are), so I put in a TL;DR at the end. Feel free to jump to that.
What is really being asked?
Let me start by saying that I agree with SevenSidedDie on this one, as far as the engine is concerned. SE has sufficient mechanisms to deal with the situation with minor consequences only.
However, I'm sure that Brian, as a mod, knows already that the engine that is SE is well equipped to deal with this. Let's look instead at the way the question was phrased (emphases mine):
- "stage an intervention"
- "someone who isn't actually having that much fun dealing with their group's foibles."
- "[someone] who likely needs a "you may want to reconsider how you go about gaming."
I don't think that Brian asked this question because he's worried that this user is going to ruin RPG.SE. It seems to be asked more out of worry for the user than for the tool. Maybe he feels (rightly, in my opinion) that we are a community of gamers, and we should care for each other.
I don't have the time to be as participative as I would like to, so I don't know who is the querent. But I "lurk" enough to know we have a set of regulars who are always around, be it asking/answering questions or commenting or in the chat.
So my best guess is that Brian is really asking:
- Are we merely a Q/A website or an actual community composed of real people?
- If we're the latter, should we care that our members might not be having fun?
- If we should, what can we do about it?
In fact, if that is right and if we were to take SevenSidedDie's answer at face value, the appropriate response would be to flag this tag as "out of scope" or whatever, since Meta—at least as far as I know—is to discuss SE as an engine, not as a group of people.
I know that SE disencourages the latter interpretation, and has constant reminders that we're simply a Q/A forum, and features designed to minimise social interaction in the website. The idea, I presume, is to put aside subjectivity (e.g. "I'll vote this up because I like SevenSidedDie"), and, a priori, I'm fine with that.
But fact is, RPG.SE is much, much smaller than other communities in the SE family. If somebody who participates frequently gives an opinion I disagree with, I'm more likely to give it a second thought than if "user31915876" does the same. Unless every user changes their name to "JohnSmith", uses a black square as avatar and a standard profile (so all that matters is the reputation), it's just too hard to ignore that there are people behind the users, and that I value some opinions more than others.
At this point, my answer becomes subjective. I'd answer my own questions by saying that (1) we're a community, therefore (2) yes, we should care—especially if it comes to a point where a mod is concerned enough to ask a question on Meta—and (3) maybe we should talk to them about our concerns.
So answering Brian's original question, as formulated by him, I think that:
Yes, I think we should care, as a community, if one of our members seems like he is struggling to enjoy gaming, which is the very thing that brings us together, and "stage an intervention" of sorts.
I'll admit I don't have a clear answer regarding how to do it. I'd recommend creating a chat room with other regular users who feel that (1) they care about this person and (2) have any suggestions they think this person could use and inviting the person in for a friendly chat. Dopelgreener has a longer, more elaborated and thoughtful response to the "how" part of the question, so I won't repeat him.
No, I don't think the person is at risk of endangering the community, for the reasons SevenSidedDie listed. And I don't think that banning the person from asking questions in this community—which is what is going to happen if we don't do anything about it—is constructive. Not for us, as a community, and not for the person. I'll concede only that maybe it'd make us more streamlined, as a Q/A website.
That said, "intervention" is a strong word—I don't think anybody should have to go out of their ways to do so. It's not a "let's come to this person's house and bring them in to get help". They are not a threat, neither to the website nor to themselves nor to others around them, they're merely not having fun by playing games. If they don't want to participate in the chat, let the engine deal with it, and that's that.