TL;DR: Close these questions as off-topic and (maybe) point them to a canonical question-and-answer.
My main reluctance about these questions is the consequences for when folks get answers wrong. I think this point has been briefly bounced around in chat in general cases, but it's especially relevant here. When a person - preferably with the help of others - is trying to help someone who may be suicidal, mistakes cannot happen. A person's life may rest on whether or not those who care about them can help.
As Shog's Software Engineering Meta post says,
This isn't a support group; y'all probably aren't trained to deal with the outpouring of grief and despair of someone you've never met and may have absolutely nothing in common with. I'm certainly not. Indeed, there's a decent chance that leaving a post like this around could end up just making things worse.
I bring to your attention the worst-case scenario for Interpersonal Skills Stack Exchange:
- A well-intentioned, trusting person comes here looking for help for a friend contemplating suicide.
- More well-intentioned folks give advice, even if they're not sure or trained.
- The trusting person goes with some of the more highest-voted suggestions, and they turn out to be wrong.
- I don't have to spell out the potential consequences.
Now, you might say, "Well, people are responsible with their votes, and won't upvote bad suggestions". Okay, sure. That's true for most cases. But going back to Shog's answer, who here is qualified to vote on those suggestions? Almost nobody. If very few people are actually qualified to answer or vote, then we'll either have a slew of incorrect and potentially dangerous answers, or one or two answers which might be right, but cannot really be confirmed.
People who use this site are/will be very trusting. C'mon, you're going on to the Internet and taking the advice of random strangers whom you may never meet or know anything about! On a different Stack Exchange site - say, Physics - people won't necessarily take advice the same way1. But here? Well, users expect that our advice is good, and they'll often take it. And that can go very, very wrong.
I think we should make individual requests for dealing with these situations off-topic.
One thing we could do if we do make these questions off-topic - and even if we don't - is to make a generic, canonical How-to-deal-with-a-suicidal-close-friend/relative post, applicable to most situations. This might have
- Links to various suicide hotlines, which could be useful to both the asker and the person thinking about suicide.
- People/organizations to contact in the event that this person the asker is talking about does start to go through with a suicide plan.
- Words of encouragement, like on Shokhet's Meta Stack Exchange post (which you linked to).
We could then close any of these questions as duplicates of the canonical one.
The thing is, I would consider the accuracy of this post to one of the single most important tasks this site could undertake. It could mean the difference between life and death. Are we comfortable with that? Maybe, maybe not. Some of the points brought up before might serve to rightfully discourage this. Who is really qualified to write this post, or judge it's accuracy? Is Stack Exchange even the right place for this content?2 This is a discussion we'd need to have if we indeed want to move forwards with this.
It could save someone's life or it could inadvertently end it. I don't know, and I'm not sure if I'm comfortable with that uncertainty.
1 If that sort of thing ever arose.
2 In other words, by placing advice on a site like this, would we be accidentally implying that folks should go to forums or unofficial sites, rather than to authoritative suicide prevention resources?