I think the main issue is that far too many people think of consciousness in terms of a binary state (i.e. consciousness is present or not) instead of a spectru

I think the main issue is that far too many people think of consciousness in terms of a binary state (i.e. consciousness is present or not) instead of a spectrum. Even in humans the state of being animals that possess consciousness varies over the course of time: new-born infants are in a different state of consciousness than 4 year old children, for example. Not to mention our regular fading in- and out and transitioning between various states of consciousness during our sleep cycle. The first important step towards a better understanding that would allow proper assessment would be to develop a sound metric to allow qualifying consciousness. Doesn't have to be precise, but a scale from say 0 (non-conscious) to 100 (awake neuro-typical sober human adult) would be a great step forward IMHO.