Because I think the nature of the attack on panpsychism illustrates why I think Reinhardt's perspective is appropriate and yours was not: panpsychism is already treading on physicists' ground. That was fundamentally his critique of Murphy: you can't step out of your lines and then declare because you're a philosopher you can't be criticized. Hossenfelder's dismissal of philosophy was specifically targeted at philosophy-that-tresspasses-into-physics, IIRC.

Regarding your final query: yes, the standard (non-panpsychic) natural sciences perspective is that reality is comprised of matter (and/or fields), and sentience is presumed to be one of many types of emergent properties (given that we've found quite a few already: bulk properties of matter, "pressure" in a gas, "life", etc. etc.).

Regarding the matter vs sentience issue, I am not entirely satisfied with anyone's account of it, nor do I have one myself that I'm entirely satisfied with. I guess the most thoughtful treatment I know of is from Patricia Churchland, who is both a very astute philosopher and a long-time student of neuroscience, to the point where her grad students often pursue "neurophilosophy" (using neuroscience methods to try to address philosophical claims; mostly not, however, about sentience). Here's a tiny bit of info along with a link to a video: https://whyevolutionistrue.com/2021/06/10/patricia-churchland-on-consciousness-and-the-brain/. I imagine that her book Conscience is also good, though I haven't actually read it--I base my comments on earlier work of hers that I have read.