I think the distinction should be on the idea of asking for experiences versus asking for advice. I'm going to try and justify it with a more rep-oriented mindset.
Bear in mind that... (from the FAQ)
Reputation is a rough measurement of how much the community trusts you.
If you're asking people for accounts of things they've done or seen done while gaming (ex: What is the most impressive skill check or roll you've seen at the table, What did you do for a Tarasque Adventure) it feels fat out silly to award reputation for answers: just because someone died fighting the Tarasque or rolled a 20 on a Bluff check doesn't mean the community trusts them any more than anyone else. It would mean sometimes awarding reputation for an account of what someone else did, or for what someone else has done to/with you. It might make them cool but it doesn't make them trustworthier.
This just parrots my answer in How should we use Community Wiki?
(...) the questions which should be CW tend to be those which are more about listing people's experiences and ideas.
Where a subjective answer deserves rep is when the answerer clearly demonstrates the kind of insight and understanding which would make me come back to them personally if I could; if the answer could potentially lead to me trusting them more.
If someone proposed a rule which fixes interpersonal problems at the table I would be sufficiently impressed that I'd remember that user and - were this the real world - I'd seek them out with more questions in the future. It would demonstrate a valuable insight which - even though subjective - leads to me trusting that answerer more, ergo they should get reputation for the answer.
This to me should be the distinction:
- "What have you done?" Questions: Asking for people's experiences and ideas should always be Community Wiki.
- "What should/can I do?" Questions: Asking for advice should not be Community Wiki; while advice is subjective, there is such thing as bad advice, which would affect "how much the community trusts you" so advice should be reflected in Reputation.