I think you're right about that. It's a fundamental aspect of how biological systems tend to be structured. Perhaps symmetry is even an indication that a parti

I think you're right about that. It's a fundamental aspect of how biological systems tend to be structured. Perhaps symmetry is even an indication that a particular structure is "cheap" in some sense. A less symmetric structure might require more information to store in the DNA, and therefore require longer evolution. If a symmetrical structure does the job as well as a more complicated structure, it's likely the simpler structure will prevail. In my experience people tend to find also non-biological symmetrical / self-similar structures striking. Something about this kind of simplicity triggers our sensory systems. It's probably more bug than feature. But it might be relevant that symmetry of biological systems often indicate health. Unhealthy biological systems are less structured, less symmetrical, and identifying sickness is evolutionary advantageous.