True crime is not far off from crime documentary. If anything I could see people arguing they're the same and it would really just come down to semantics.

To me, a " crime documentary" is a show or episode covering a specific crime or suspect. A True Crime podcast (or show, vlog, etc.) tends to cover a new crime or suspect each episode.

If anything, I would argue True Crime shows are a series of mini-documentaries so-to-speak.

Another thing to consider would be production value. When I hear "Documentary" I think of something I would see on TV or a streaming service. In other words I think of something backed by money.

When I hear "True Crime" I think of podcasts or vloggers. Typically a person or small group of people doing their own research and producing their own content.

A True crime podcast I'd recommend would be Small Town Murder. My wife will listen to it as we're doing chores around the house and I would catch myself paying attention from time to time.

Crime documentary is the product, True Crime is the genre

True crime means what it says. It's crime that happened as opposed to fictional crime. In this context it usually means things like podcasts about true crime. It's only different in that it's a larger umbrella than just documentaries.

Edit: Fix contradictory typo