Plants are frequently ignored or undervalued. There may be more species of insects, but not more diversity . Second, I don't think most people would be happy losing the species we currently have, even if they are replaced by new ones. At the very least, we don't want to contribute to any extinctions. I think there is a lot of confusion about facts and behaviour.
Facts provide our surest, most solid foundation for action.
It is detrimental, and completely unnecessary, to compromise on matters of fact . The confusion arises when we consider actions . Believing that facts imply that certain actions must be performed, some people compromise their statement of the facts. We may know that a given development will drive a species to extinction, but what we do about that fact is still a moral decision. Scientists are usually honest in their statement of their findings, but in their choice of what to study , not always.