Light and reflections are part of the material
Polished metal reads mainly through what it reflects. Diamonds and gemstones also respond to their environment and to light. So photorealism isn’t only about good materials; lighting and environment are part of how the material is perceived.
Commercial photorealistic
For a catalog, a website and variations, the right level is often a commercial photorealistic render: high-quality, credible and consistent, yet efficient enough to produce a series of assets. Consistency can matter as much as capturing every possible detail.
High-end / near-photographic
For a hero image, a campaign or a key asset, a larger investment in light, material, composition and finish can be justified. The question is where the added quality is truly visible and creates value.
More realism isn’t always more value
Trying to make every image especially dramatic can hide the piece or create an expectation that doesn’t match the product. A good render should serve the jewelry, not the technology.