If the answer is nothing but personal experience, but results in it completely solving the original problem then it is definitely an answer.
I've seen this before. When I last used FlugelBinder3000 software I had to ratchet the wurzle and everything just worked.
Is definitely an answer. It solves the problem. What more could you want?
It could be nice to say why, but you get a solution at least.
Conjecture, such as
this might work... I tried it once but wasn't sure what happened but the problem eventually went away...
Isn't as helpful. At best this sort of thing is a suggestion of a possible fix and should be a comment.
When applying flags you should read the help text that goes along with it.
This answer has severe formatting or content problems. This answer is unlikely to be salvageable through editing, and might need to be removed.
Something that is in some way attempting to answer the problem but is completely unintelligible would fall under the purview of VLQ. As with a lot of things though, what is unintelligible to you might be understandable by another. Again, judgement call time.
Your example is definitely editable and salvageable, it could be made to sound more authoritative quite easily through editing. To me it is definitely stating what they believe the problem is.
Leave a comment, downvote if you must, but personally I don't think it is unsalvageable.