Aside from the fact that you can actually polish a turd, it's a bit of scatology that might potentially be best flushed away. It came up in an answer to another question and I feel like it's worth discussing alternatives.
It might be nice to have something less colloquial and talking about the content.
What might be some less crappy ways we can talk about posts that aren't really salvageable?
I'm not sure we can find a better metaphor. I do understand nobody likes their post being called a turd, but it's difficult to find something which is worth less than sand and still not belittling. One metaphor I do like is this: desperate attempts to fortify sandcastles to save them from the inevitable tide. Sandcastles may be beautiful in the eye of the children who made them (just like new users' posts here) but are barely more than humps of sand to others.
My two cents would be that we skip the metaphor section and settle for something more direct, 'content beyond repair' or something. But I'm sure native speakers will come up with something better.
Let's try to go back to the source. There are two words to consider.
The term "turd polishing" is just really accurate, in this context, and really catchy, hence used so widely.
But there is other term which will still be accurate, most of the times: cosmetic repair.
Edit that, for example, fix the grammar in a post with bad quality, is exactly this: only cosmetic, and failing to fix the actual issue in the post.
So I suggest to switch over to cosmetic repair instead of turd polishing whenever discussing such things.
Usage example:
Bob: Did you see this edit by Joe? Such a waste of time.
Jane: Yeah, it's just cosmetic repair, that answer can't be salvaged. Should we let Joe know?
Disclaimer: this term popped up while I was looking around, in one of the answers to Phrase to describe a fix that doesn't address the underlying issue?. After some thought, decided it can indeed be fitting.
We're talking here about phrases for pointlessly dressing something up. One of the oldest and most well known is
You can't make a silk purse out of a sow's ear.
That seemed to be superseded by
Rearranging the deckchairs on the Titanic
And popularised in recent years by American politicians, though not invented by them was
Lipstick on a pig
Fundamentally you need something that gets across the pointlessness of what's being attempted and ideally the missed opportunity cost of spending that time doing something more productive such as answering a better question that doesn't need such polishing in the first place.
Credit of the following goes to mickmackusa
unwanted posts
Sheer acumen.
edit to unwanted posts
