It sounds like your local AHJ has adopted additional requirements above and beyond the Uniform Plumbing Code, this isn’t out of the ordinary but that seems excessive when a hot water recirculation pump on a time-of-day timer would be far more cost effective, it’s a $200 pump and an extra 20 feet of water supply line.

Does someone in local government own a plumbing contractor or plumbing supply company? That’d be my guess anyways.

There's actually no plumbing code (checks) for my house. I could drop my poop right out the back of the house and pull my water through lead pipes from a mosquito swamp into my sink. As long as it is immediately heated it is fine. It is literally the only requirement.

My permit explicitly says they will check absolutely nothing but how far the house is from the property line and that I have immediate hot water.