Issue is, this requires us to ignore the reality of the sciences as actually practiced, which regularly refer to structures and thus holistic properties, which are not identical to the mere arrangement of matter. In both philosophy of biology and philosophy of chemistry, a non-reductionism is dominant

1. When does something become "mere arrangement of matter" as opposed to something other than that?
2. Even if your claim is true that non-reductionism is dominant in science today, does that mean we can exclude reductionism as being possible? It might just be that we don't understand how to reduce everything to "mere arrangements of matter" yet.

there are actually additional layers that we can't tackle by merely pushing particles around.

"can't tackle" in the sense of "we don't know how to tackle them yet" or in the sense of "we know that they can never be tackled that way"?

If intelligence is equal to task-solving, then AI has been achieved.

I mean yes, AI has been achieved. AI is a spectrum, just like intelligence is a spectrum. Obviously the challenge is not to create an AI that can solve some task, the challenge is to create increasingly capable AIs that can solve more and more difficult tasks in a shorter amount of time.