I think it's the phrases 'some coordination' and 'company the size of Apple'. It's rarely the case (well, hopefully?!) that a fix is as trivial as 'oh yeah, oops, let's delete that `leak_data()` line' - it's going to involve multiple teams and they're all going to think anything from 'nothing to do with us' to 'hm yes I can see how that happened, but what we're doing in our piece of the pie is correct/needs to be so, this will need to be handled by the [other] team'.

Not to say that people 'pass the buck' or are not taking responsibility exactly, just that teams can be insular, and they're all going to view it from the perspective of their side of the 'API', and not find a problem. (Of course with a strict actual API that couldn't be the case, but I use it here only loosely or analogously.) Someone has to coordinate them all, and ultimately probably work out (or decide somewhat arbitrarily - at least in technical terms, but perhaps on the basis of cost or complexity or politics or cetera) whose problem to make it.