cry havoc

Yes. When I first watched this I was wincing for the same reason, and I think that may have been why she chose to leave it blank in the end. But Streep's actually said in many interviews that she didn't consider Eleanor a villain -- her take on the character was that she was an extremely righteous, patriotic, self-sacrificing person; not at all an evil woman, just tragically misguided. I do totally grok that the accent was problematic because most people would have read it as the Eebil Southerner trope, but on reflection I think the intent may have been less about evil and more about insincerity. Eleanor is an extremely charming, warm-and-friendly sort of person, the sort of woman who smiles almost constantly, whether or not she's truly glad to see you. And I think that that type of excessive, fake sweetness is something that Northerners perhaps associate with Southern women. (Hopefully it goes without saying that I don't subscribe to this.) Which I suppose isn't much better, really, but my point is that the actress actually kind of loved this character, and I doubt that she would ever have meant to present her as a villain.

Now that you've pointed it out I can hear what you mean about the shift she makes halfway through -- in retrospect that was what caught my ear about that first "why." I think I'm just going to pin down her accent as being a soft Richmond one, with the caveat that her mother was from Connecticut and her dad's speech was heavily influenced by Washingtonese (he was in politics as well).

Thank you so much for helping me puzzle this out! Getting people's voices right is always really hard for me, so this was a crucial bit of my process.