I also agree that your second paragraph is the logical conclusion of a materialist starting point - that is, the physical universe is all there is. There is really no other conclusion from that starting point.
But that leaves us with no free will (automatons don't decide anything).
It leaves us without love. (Real love is choosing to do what's best for the other person, and we can't choose. And even what we feel as love is just neurons and biochemicals doing canned mechanistic responses.)
It leaves is with no morals. (When a rock falls off a cliff, you don't say that it should have fallen differently, or not fallen at all. We don't think morals apply to mere material objects that are merely obeying the laws of physics, no matter how complex they are.)
It leaves us with no truth. (Our brains evolved to get a good enough answer fast enough, not to discover truth in any absolute, platonic sense. And when we "think", we're just letting those neurons do what they're wired to do, without knowing all the bugs in the hardware.)
But we also have years of experience of what it means to live as a human being. We experience choosing, loving, knowing that some things are right and others are wrong, and discovering truth. We know, via first-hand experience of living, that "complex automatons" does not adequately describe human life.
It's kind of like putting on a t-shirt backwards. It covers all the places that need covering, but it just doesn't fit. And no matter how you try to move it around and re-arrange it, it still doesn't fit. In the same way, the logical conclusions of the materialist starting point don't fit our experience of what it is to live as human beings.
This leaves us with two possible responses. The first is that, out of random chance, the universe has created complex automatons that have the experience of being (and the desire to be) more than automatons - to be genuinely personal, rather than just the impersonal plus complexity. Those perceptions are wrong, and those desires will forever be unfulfilled. It would be cruel, except that the universe doesn't have motivations, and to to call it cruel is a category error.
The second possibility is that the materialist starting point is mistaken - that there is more than merely matter and the laws of physics. This is what I believe. More strongly, I believe that our experience of living as humans is evidence that the materialist starting point is mistaken.
When the Bible says that God made man in His own image, it is saying something about this 21st-century argument. It is saying that there was a first there was personal, not impersonal, and that God (someone, not just something) created humans to also be someone, not just something. And therefore, our experience of being personal rather than impersonal is in line with what has always been.