While philosophy is too often irrelevant because it too often operates in a vacuum, evolutionary theory provides a more adequate means whereby to assess supposedly “difficult” philosophical issues. As we’re a primate group species it would be extraordinary if we didn’t have hardwired mental modules that selection pressure over the eons has crafted to enable us to function reasonably well in groups. Of course today our world is far more complex than the world for which we’re adapted (the African savannah and the primordial forests of Eurasia) but from an anthropological perspective this is merely something for which appropriate adjustments need to be made.
Morality isn’t “out there” any more than love is “out there.” We humans fail consistently to distinguish between our vague mental constructs and objective reality and so we get ourselves into intellectual incoherence. We don’t need philosophy to understand why people act as they do relative to other people’s behavior; we just need to understand that we’re the products of evolution. When we do this we immediately understand there are modules that will be helpful for group cohesion and we also immediately understand that it is quite impossible for any morality to be anything other than relative. Fortunately even philosophers themselves worked this out eventually, and Phillipa Foot’s famous trolley car problem is the most accessible proof of the fact no set of moral rules can be adequate across all possible use cases.