From a data perspective, it would seem that there would be some major implications for this particular deal. If Stripe can gain a window into the purchasing habits and volumes of Amazon’s massive customer base (not the actual items, but the size and frequency), it seems like it’d be a major boost to the depth and breadth of its machine learning models. For Amazon to give that sort of capability to another company — which seems to have begun a few years back — seems quite remarkable to me.
On this same line of thought, I would assume that Apple has been working to bring more and more of its payment infrastructure in-house, as it’s a major area of data leakage (regardless of whether the data is merely used to train fraud prevention models, or to do something more “interesting”). Maybe someone with actual knowledge on these matters will comment here…