1. It's a genuinely useful term, descriptively named, for which no good succinct alternative exists: eg, "outrage porn."
2. A genuinely useful term, poorly named, but excusable because it already has an entrenched history and community using it: eg, "monad" in functional programming.
3. A confusing term, poorly named, for which many good alternatives exist, but which continues to thrive on meme status, or for political reasons, within a particular community. A lot of marketing and business slang, and PC terminology, falls into this category.
So I think it's valid to criticize slang in category 3. That is, not all slang is created equal, or for equal reasons.