I think you’re right about constructive feedback. People here, unlike facebook, are generally very courteous.
And I think the fact that the complaints are so extremely minor (and, IMO, 90% dismissed by Harmy’s gallery), shows just how close to perfection this turned out.
But there are indeed people on spleen and facebook who are imagining that the contrast is ‘ruined’ throughout the whole film. Harmy pretty much shut that idea down with his gallery, and it is more likely that some of those people don’t understand what the 35mm shots are, or how incredible it is to have them in as good a state as this.