There's clearly a spectrum of consciousness between us and insects, there is no one clear-cut threshold, and some people are lower on it than some animals (see some neurological problems). Therefore arbitrarily deciding to put a strict care/don't care threshold on a species border is irrational. It makes much more sense to have a care/don't care spectrum, and not to limit it to one species.
I’m not so sure its clear that there’s a spectrum of consciousness. We have no way to observe consciousness (other than our own). For all we know, ants (or even trees or rocks) might well be just as conscious as us. We don’t have any evidence that they are, but that’s largely true of mammals and even other humans too.
