There's things like the Anduril Bolt. They cost like 100x as much as devices the Ukranians are building from cardboard. Another major innovation is TOW style fiber optic control which is immune to electronic countermeasures. There's definitely a lot to learn, but sadly necessity is the mother of invention and not since WW2 has manufacturing cost really been a serious concern for US defense production. Seems like we'll need a really big war to make that essential, and then there's an open question whether we'd actually be able to do it given that nobody knows how to do anything anymore.