I agree that it's misleading but harness is now an essential part of LLM's effectiveness. It's safe to assume that LLM-alone-AGI is not coming anytime soon, given most of the frontier LLM vendors are developing their own harness.

Also the training dataset is proprietary and they'll drive the LLM's behavior, so it make sense for the vendors to invest in the harness and bake in prompts that work best with their models.