There's no need to invoke philosophy here. It's pretty well accepted that an ecosystem with less biodiversity is more fragile, and from that perspective the ext

There's no need to invoke philosophy here. It's pretty well accepted that an ecosystem with less biodiversity is more fragile, and from that perspective the extinction of a species is a concerning event, particularly if the extinction was accelerated by human actions. If new information indicates that a species or group of species is in much greater danger of going extinct than was previously thought, then it makes sense to prioritize conservation efforts for those species more highly.