Well, the image is clearly non-free (no argument from me then or now) but I think was a good faith disagreement over #1; whether the image was "necessary" or not. Your deletion rationale did not address this disagreement. If you think the "delete crowd" had the stronger policy based argument then you should be able to articulate the reasons why. I'm told someone to take it to Deletion Review many times; this is always a valid threat because DRV is such a pain in the ass so that's usually the end of it. A discussion of that length and complexity merited a more appropriate response.