Remember kids if you are an immoral asshole you can still buy your way into being right.
We have plenty of such righteous asses on here. I am on bernie's flag trail myself, wasting his VP with my comments around the platform. I have a couple of more of those angry haters going around downvoting my comments, joining the fun. I sometimes vote them back up for visibility, but for the most part? Don't care.
As for this specific issue, I disagree with you. In part. "Steemit should not be about soliciting nude images." Well, steemit can be about anything you want to it be, really. If I choose to post my breasts on steemit, it's totally my choice. In addition, the Internet is the Internet. People should know better than to post their nudity online then complain if they suddenly regret it. It's why I make sure only post my GOOD nudes. :)
I do agree that flagging unrelated posts is petty, abusive and pretty pathetic. On the other hand, I also think you should not regard this silly competition as something that endangers the foundations of steemit as a community or whatnot. It's a silly content, with silly entries (did you see the plush boobies? I died!) that is all about having fun. Not having fun? Don't upvote? Having non-fun? Flag it as hard as you can and mute the user who published it.
Bottom line: Ignore the haters. Let them flag. Don't take steemit too seriously or it'll just cost you time and emotion.