Procedural Mesh Generation is the act of creating meshes through code. This is heavily used in cases like terrain features where you can efficiently modify meshes at runtime or creating math-based effects. You can also save on memory and increases performance by cutting out geometry the player can’t see and reducing the overhead of instance counts as each procedural mesh would be a singular instance. The last two points is what can give it an immense benefit over just using parts and especially having to deal with intersection clipping.
I would say NSFW content would be a concern with this, but given we have free reign over parts, I don’t expect anybody to really abuse it more than what you can do with parts.