Furby , BA was well within their rights to do nothing for you, as: 1) these were separate tickets; and 2) BA did not cause the misconnection (they were not the late-delivering carrier). But AA did right by you -- albeit not as seamlessly as it should have.

If I were traveling on separate AA/oneworld tickets these days, I think that I would carry a printed copy of AA's newly-revised protection policy with me.