"J2's probably the only module we've done that doesn't really mesh as well as it should with Golarion. It still works fine as an adventure, but Dragons Revisited should be considered the primary source on dragon lore for Golarion. We won't be adhering to much of the elements of J2 at all going forward." Just figured it should be noted so that any discrepancies between J2 and anything else, to use the other source.
Erik Mona noted in the same conversation(in the original chat discussion on the topic) that J2 is still canon. Nothing in subsequent dragon lore has refuted or conflicted with the account of Dragonfall in J2. Sure, they haven't mentioned it at all, but they haven't come out and said it didn't actually belong in Golarion. They saved themselves some by not declaring where it was and leaving it pretty mysterious. I don't think we need to point out errors in their editorial continuity during the first year of production. I'd also rather not set the precedent of noting all the commentary editorial staff makes about the products on these pages. If they are writing errata, that's one thing, but otherwise, I don't think this is the place for it.