At the moment, there's only two close reasons we can use for them:
- Off topic because we don't provide learning resources
- Primarily opinion-based
Neither of those really gets at the heart of the problem with the question. If we mark it as a learning resource question, the OP can rightly argue that they weren't asking for resources, but advice (and the link in the close reason can easily reinforce the misunderstanding). If we mark it as opinion-based, we fail to convey that questions about learning methods are still categorically off-topic (due to not actually being about the language); and indeed, some questions about methods can be answered fairly defitinively.
It seems to me like it would be a good idea to explicitly include questions about learning methods under the 'questions asking for learning resources' heading, perhaps rephrasing it something like this:
Questions seeking resources or advice about learning Japanese are off-topic here, but you may find our list of learning resources helpful.