Here are my current thoughts (others may disagree)...
Pros and cons
Does allowing resource questions harm the site? In some ways, yes.
- There are multiple issues (see below), including broken links, obsolete answers, link-only answers, opinion-based answers, overly specific questions, and Google requests. (Although not all resource requests have these issues.)
Does banning resource questions harm the site? In some ways, yes.
- They're common questions among people learning Chinese, they might facilitate learning Chinese, and they sometimes require the expertise of the site's users (cf. Wrzlprmft's post about photography). We lose this by banning them.
- The current "ban" is simply not working; it's enforced inconsistently and unfairly; it's too much effort and heartache.
At this point in time, I'm leaning towards "resources = not off-topic". This is not to say that we don't close them (as many of them are indeed problematic and worth closing), but I don't consider them close-worthy for the sole reason that they are a resource request. We still have the usual close reasons: Duplicate; Needs details or clarity; Needs more focus; Opinion-based, along with write-your-own off-topic reasons, and migration to Language Learning.
There are options we can consider: "Forward duplicates" are possible, e.g. if the answers are obsolete, we can re-ask the question, and close the old question as a duplicate of the new question. We can convert answers [e.g. link-only answers] to comments. We can add a notice like at Physics.SE explaining the expectations for resource requests. We could simply delete old resource requests after a certain time (e.g. 1 year): the OP gets their answer, and we don't have to waste time curating broken links and obsolete resources.
Only two language sites have a close reason for resources: Japanese (49 Qs) and Chinese (133 Qs). At neither site is it enforced consistently, which indicates how unpopular (or unclear) this close reason is. The others sites are: English (77 Qs); German (119 Qs); French (141 Qs); Spanish (33 Qs); Russian (25 Qs); Latin (72 Qs); Italian (40 Qs); Portuguese (8 Qs); Esparanto (21 Qs); Korean (32 Qs). This is proof of concept that the site won't fall apart if we allow resource requests.
The current close reason links to Resources for learning Mandarin Chinese. I'm not sure where this is going, but my opinion is that the linked resources page is poorly maintained and contains many useless resources. (The close reason is also pointless because we can simply close as a duplicate.) I feel this definitely needs to change. I'm not totally against having a central question like this (maybe it's good advertising), but if we're going to create a up-to-date version, we need to address obsolescence and quality in some way.
What makes a resource question good or bad?
Bad resource questions...
...are vague: It doesn't request particular resources, but a unspecific "what resources can solve a problem?" There are many possible "correct" answers.
- E.g.: What resources can help me get started learning Chinese?
...are too broad: It's specific, yet there are still many possible "correct" answers.
- E.g.: Is there an iPhone Chinese dictionary app?
...are too narrow: It is so narrow that finding the answer is overly difficult and benefits only the OP.
- E.g.: Is there a pdf version of the textbook لا أحد يحب الألم بذاته which was used to teach Chinese in Saudi Arabia in 1985?
...are about the OP: The OP is after some personalized recommendation.
- E.g.: What resources can I use to improve my speaking and listening (currently HSK4) before my 1-month trip to Guangzhou?
...are a Google request: The resource exists if and only if Google says it exists.
- E.g.: Where can I find example solutions to my Chinese textbook 发展汉语?
...have an unspecific quality requirement: The OP is somehow unsatisfied with the first Google hits, but doesn't specify what it actually wants instead. They often contain the word "good" in the title.
- E.g.: What are some good resources for learning calligraphy?
...request link-only answers: It is likely to be answered only by a link, and that link might break over time (or redirect to e.g. NSFW websites).
We waste user time checking and maintaining these links.
- E.g.: Where can I download past HSK exams?
...request answers which will become obsolete: It asks for resources (particularly webpages, apps, software, etc.) which will become obsolete quickly, even if the link doesn't break.
- E.g.: Which apps help with basic Chinese pronunciation?
...are irrelevant to learning Chinese: It asks for a resource which is largely irrelevant to learning the Chinese language.
- E.g.: Is there a Chinese version of Introductory Calculus (2nd ed)?
The expertise required is often more "Google-fu" and less "Chinese language". In some cases, answers can also be exploited for advertising.
Good resource questions...
- ...facilitate learning Chinese: It asks for resources which facilitate learning the Chinese language, which is helpful for others.
There's also something to be said for using such questions to advertise the site (via links shared around the Internet).