It's because the term itself got overapplied by people critical of LLMs -- they dismissed all LLM-assisted coding as "vibe coding" because they were prejudiced against LLMs.

Then lots of people were introduced to the term "vibe coding" in these conversations, and so naturally took it as a synonym for using LLMs for coding assistance even when reading the code and writing tests and such.

Also because vibe coding just sounds cool.

Like people using “bricked” to signal recoverable situations. “Oh the latest update bricked my phone and I had to factory-reset it, but it’s ok now”. Bricked used to mean it turned into something as useful as a brick, permanently.

Words don't have meaning in 2025.

A negative but courteous remark is "slamming", a tweet is an "attack", etc.

So yeah I'm not surprised that people conflate any use of AI with vibe-coding.