Water conservation vs. 60% livable plants in your backyard

I live in the Mesa Pines North section of Canterberry Crossing in Parker and redid my backyard this summer. We wanted to minimize the amount of grass and plants to reduce our water bill and the yard is on a slope so most of the area is unusable anyway. My HOA has a rule that is not enforced for existing yards which states I need 60% of my yard covered by livable plants. I sent them pictures of houses in my neighborhood, some of which are all rocks and a concrete slab for a patio, and asked them why I'm held to this standard. I was told I could file a complaint against one of my neighbors if I wanted to and they gave me a link to the form.

Every summer we hear about how important water conservation is yet I had to design a yard I did not want and deal with $300 a month water bills to keep the grass and plants alive. I hope this changes soon so I can redo my backyard without any repercussions from the HOA.