As a general rule:
- Downvoting is for when the answer is perceived to be "low quality", people may choose to leave a comment explaining their downvote or not.
- Commenting is for clarifying or requesting changes where you don't feel that you can edit.
- Editing is for when you think an answer can be improved (without destroying the substance of the answer) and you think you know how to do it.
- Flagging is for when you want one of the moderators to take a look at it, e.g., because it is something that lowers the overall quality of discourse (just a link), is a violation of the rules in some way (e.g., spamming, personally attacking other users, etc), or is entirely unrelated.
So what we have here is Dave Liepmann saying that it "doesn't address the question" because the field is larger and more complex than something that can be easily summarized. Your post was clearly attempting to remain on-topic and address the core of the issue, so it isn't the sort of situation that moderators are likely to step in on.
In this particular case, if you were talking about gardening tips in a question about conflict resolution that would be flag-worthy, but saying "-1, this is more complex than you make it out to be" is more of something that makes for a good comment rather than a flag (because it isn't moderator-actionable).