Over-engineering in nature is indeed a conundrum for evolution, and a serious challenge for evolutionists. They see the problem this way: How and why would natural selection select for an attribute for which there is no survival advantage, given the living conditions and lifestyle of the creature in question?
There’s a fundamental principle at issue here. If something is over-engineered, does that not mean that it must have been engineered in the first place? And if it was engineered, does that not imply an engineer who designed and built the creature?