Consciousness seems to be a word that is poorly defined. You see this a lot, and one of the more popular instances are questions like "is cereal a salad?" It plays on the fact that the definition of a salad is relatively loose, and because it's loose items which aren't usually associated with the word do actually fit the definition.
Consciousness feels much the same way: there's a very loose definition which is colloquially understood by almost everyone. Asking whether humans are conscious (and I know you were being somewhat facetious) feels like it fits into this frame of thought. Consciousness, as most people understand it, is something which almost all people possess and something like a rock cannot possess. I think it's perfectly fine to argue that a rock or a tree can be conscious in some way. However, this does require a precise definition of consciousness in order to clearly differentiate it from the loose colloquial notion that most people hold.
Consciousness feels much the same way: there's a very loose definition which is colloquially understood by almost everyone. Asking whether humans are conscious (and I know you were being somewhat facetious) feels like it fits into this frame of thought. Consciousness, as most people understand it, is something which almost all people possess and something like a rock cannot possess. I think it's perfectly fine to argue that a rock or a tree can be conscious in some way. However, this does require a precise definition of consciousness in order to clearly differentiate it from the loose colloquial notion that most people hold.