There's already one well-voted example on the proposed questions, and it looks to me like a perfect example of a question that should be on topic.
Can learning kanji speed up the process of learning spoken Japanese? (+10 votes at time of posting)
- It's clearly about language learning
- It references a feature of a language. In theory, answers could be applicable to or based on experience with other languages with similar features (e.g. Mandarin, Cantonese)
- It's about how to learn something in a language, not what something is in a language.
...and for me, the crucial one for deciding such questions:
- If I was in a room with someone A) who was an expert on the Japanese language, but was not necessarily skilled or knowledgeable in language learning (e.g. a professor of Japanese from a Japanese university), and someone B) who was an expert on language learning, wasn't an expert on Japanese, but had experience teaching or learning languages with similar features (e.g. an experienced Cantonese teacher), I'd ask person B first.