> We pretty famously can't prove that humans are conscious

While I wouldn't call this statement flat-out wrong, I think it's unclear and possibly conflates multiple concepts that exist in different domains:

1) The hard problem of consciousness, which is a philosophical problem that asks "why do we have subjective experiences at all?"

2) Solipsism or hard solipsism, which is another philosophical concept that asserts that only one's own mind is certain to exist and there is no way to prove that any other minds besides one's own aren't just a figment of one's imagination.

3) The science of consciousness, which is the scientific study of how and why consciousness arises in the brain.

The first two are concepts existing in philosophy, while the third is in the domain of science. We absolutely can scientifically show that consciousness is a product of the brain of humans and that one's consciousness can be altered by making modifications to the brain (e.g. via physical or chemical means).

So your statement is at least unclear. Depending on what you mean by "prove," and whether you're speaking about philosophy or empirical/scientific evidence, it may also be incorrect.