When programmers came about, SO (StackOverflow) was already a well-established site for technical questions. It has a hard line on questions that are difficult to answer directly, either with simple logic or code, or references.
Programmers was created (or so it seemed) with a similar goal, but for not directly technical questions. Typically things that are too high-level and not detailed enough for SO end up there, e.g. questions about architecture, design patterns or paradigms (and many others).
What seems to have changed is that the moderation policy has become ever more to the letter, closing any question which doesn't seem to fit the site. The problem with this is that most of the policy (the "FAQ") is in line with that of SO, where it works great. I honestly don't think that high-level, architectural questions can be answered in a 100% correct way; they are often too fuzzy, involving trade-offs that are different for different organisations and people. So basically, if any question comes along which has no single "correct" answer, it is likely to be closed. This is a bit of a problem, because I for one would love to read about the (highly educated and refined) opinions of some great developers. Apparently that isn't allowed, however, only "facts".
This is exactly what happened to Literature.SE and a couple of other sites I dipped into (although Lit.SE was my most active, and I was in the top 10 users there before it closed).
The moderation was harsh and it led to questions being mundane, tedious or boring - and a race to get the "right answer" in (with little effort on quality). Opinion was stamped on and it was clear that SE was looking for mindless answer-drones and not a community with opinions and views.
Unsurprisingly, Lit.SE died a death after less than a year.
It wasn't just the moderation policy, the actual purpose of the site was changed from anything "Not Programming Related" to "conceptual questions about software development". That led to moderators shutting down the active community that had formed around career development, office politics, equipment, etc.
The original version of Programmers was called "Not Programming Related", and it was created as a site for anything and everything that didn't fit Stack Overflow (What's your favourite programming cartoon, etc).
What you are describing is actually the current scope, that seems to be working just fine. You're right that questions that fit within the site's scope rarely have a definitive answer, but a definitive answer is not what we are looking for, just a finite and somewhat limited set of good/great answers.
Here's a few recent example questions that probably explain what the site's about better than I could ever:
Yeah, those are some great examples. Correct me if I'm wrong, but wasn't the most viewed / highest reated question ("what should every programmer know about web development") closed at one time due to being a "polling" type of question? Here's the link:
Personally, I've found that some of the most interesting and instructive answers have been quite opinionated and not really fact based. Sometimes these lead to (heated) discussions of their merits, which lead to some insights into the various opinions. I would almost say that in software architecture, most areas are gray (and those that are black and white are trivial or uninteresting). It's just unfortunate that these types of questions and answers run the risk of being closed.
What I'm really saying is: I get the need for moderation, and yes, perhaps some questions are not a good fit for the site. But I'd still love to have some place where developers express their opinions and are challenged to justify them.
It was closed and re-opened a few times (full revision history: http://programmers.stackexchange.com/posts/46716/revisions).
Every time that question got shared somewhere, it started getting crap answers instantly, everyone ignored the fantastic community curated top voted answer and went ahead and added yet another one liner saying "learn css".
No one wants that question closed, but at the same time only a handful of people actively prune it every now and then. Right now it's open, but if it starts generating crap answers yet again, we might close it. And then silently re-open it when no one's looking, hoping that the next troll that visits the site won't notice.
However, keep in mind closed doesn't mean dead, we have lots of great (but closed) questions (http://programmers.stackexchange.com/search?tab=votes&q=...), if at some point a question becomes incredibly troublesome, closing it is the easy - and reversible - fix. Killing crap answers, rewording the question to be a bit more specific, etc, is a very slow process, but it happens.
Actually their motto is to make it a question and answer site and not a discussion site.
The issue with that is, the answers that follow depend on the question. If the question cannot be answered as a clear cut fact then an discussion is inevitable. Also some questions by their very nature attract discussions and they turn out to be the most interesting ones.
As somebody else also mentioned, some topics just can't have a clear factual answer like religion, literature etc.
The problem with factual answers is, there is only that much you can do with general problems that everyone face. Once those questions(problems which every one face generally) are answered, your site turns to a knowledge repository. And then the site traffic greatly depends on specific problems faced by people and most generally nobody else gets interested in those.
That rationale makes sense for Stack Overflow. It makes absolutely no sense whatsoever for Programmers Stack Exchange, which is supposed to be for the "big questions".
Programmers was created (or so it seemed) with a similar goal, but for not directly technical questions. Typically things that are too high-level and not detailed enough for SO end up there, e.g. questions about architecture, design patterns or paradigms (and many others).
What seems to have changed is that the moderation policy has become ever more to the letter, closing any question which doesn't seem to fit the site. The problem with this is that most of the policy (the "FAQ") is in line with that of SO, where it works great. I honestly don't think that high-level, architectural questions can be answered in a 100% correct way; they are often too fuzzy, involving trade-offs that are different for different organisations and people. So basically, if any question comes along which has no single "correct" answer, it is likely to be closed. This is a bit of a problem, because I for one would love to read about the (highly educated and refined) opinions of some great developers. Apparently that isn't allowed, however, only "facts".