I dont know if AI has much to do with it (who knows), but computers are indeed vastly than before, better at calculating trajectories, etc.
I used to work with a UC Berkeley Astrophysicist, who specialized in orbital dynamics. We hired him to do curve fitting algorithms for inspecting parts with complex curves. A very similar problem, and he was upbeat about ABM systems (given the requisite computing power).
Yeah., Dropping a warhead from space and depending on gravity to hit the correct target would require really complex math and with A.I. it’s now possible.
I doubt very much any system could detect, correctly, falling metal with no heat signatures from propulsion.
Keeping in mind the government was squawking about Russia and China putting nukes in space.