Try remarking that apple pie is tasty. I’m sure I would agree with that.
And if you would have inserted “considered to be” into each of those sentences that I put “why” in front of, I would agree to that too. If this is what you actually meant, then yes, tragically this is so.
I don’t see how this is relevant to us here, though. Other people may be depressingly easily convinced by religious or spiritual answers, but you and I are not. Why then should we, here, in this thread, consider their unsupported explanation a worthwhile answer? Religious answers do not exactly have a reputation for turning out to be right when science finally sheds light on the mystery. If their answer is really the only one we have, then perhaps we are better off with no answer at all.
Your last comment confuses me. Isn’t this just a matter of definitions? We, speakers of the English language, are the ones who decide the criteria for sentience. This is not something one would expect to be an insurmountable hurdle to science.
Once we have defined sentience, we can then proceed to evaluate how it works.