"A rose by any other name would smell as sweet" is from Shakespeare's Romeo and Juliet. It means: what matters is what something is, not what it's called.
I feel like this phrase has a very positive connotation to it: what matter is not what this fantastic thing is called, it matters what it is. Is there another common phrase, metaphor, or idiom I can use that has a more negative connotation? I'm looking for a phrase that says that it doesn't matter what this bad thing is called, it's still the same bad thing.
An idiom like, "lipstick on a pig" or "sugarcoating" means making a bad thing seem less bad. This is not what I'm trying to convey.