I'm increasingly suspecting that it would prove absolutely nothing, and I really hope we can continue developing ethics without any "empirical proof" for its necessity.

For example, growing up, my bar for "things that must obviously be conscious" included anything that can pass the Turing test, yet look where we are now...

The only reasonable conclusion to me is probably somewhere in the general neighborhood of panpsychism: Either almost everybody/everything is somewhat conscious, or nothing/nobody is at all.