So, because this is pulling on strands of precisely why I like the 2005 bestest, the thing both of y'all are hitting on is (imo) one of the most successful aspects of the 2005 as an adaptation, which is that it walks the fine line between accuracy and accessibility VERY well.
What I mean by that is, yes it’s correct that the hair down/open cravat looks are DEEPLY scandalous in terms of actual historical accuracy. At the same time, the average audience member isn’t necessarily going to know that (as we can see by the number of people who watched S*nditon and were like “yeah this is cool no issues” even tho main girl’s hair was down and loose 2/3 of the time).
And OP is right in pointing out that the two scenes parallel each other, but behind that is also the fact that this is really the only time Elizabeth’s hair is down in the whole movie. It sticks out visually, and even an audience member who might hear “she walked three miles” or “her hem six inches deep in mud” and think “ok? So what?” is going to see Elizabeth, flushed and sweaty, hair down, among the prim and put-together Bingleys, and is going to clue in that Oh Okay so she’s being Inappropriate. And then the same thing later on with the ending- Darcy has never looked this disheveled, it’s visually extremely salient, and it’s communicating what it needs to.
It’s clear that these moments were deliberate choices because, as a rule, the film is very much aware that Lizzie and Darcy are extremely preoccupied with social propriety. Lizzie is constantly reining in her family and being embarrassed and judging people. It’s not like the film suddenly forgot that for this one scene, it’s just that it took a liberty in order to emphasize the shocking nature of her behavior without having to have everyone sit around expositing about how Scandalous and Uncouth Lizzie was being.
I went back to the book and it takes, eh, probably a page of back and forth between Mrs. Hurst and Caroline to express how shocking Lizzie was, and it’s focused mostly on the mud and her being alone (although they also comment on her hair being “blowsy” and “untidy”!) A page of back and forth is, like, a LOT in terms of movie time, when the same thing could be expressed in a second just with the somewhat jarring visual of Lizzie, hair down and wild, obviously not Being Proper.
(I could honestly write another essay entirely on how the second proposal is less of a “these are events that took place” and more of a dreamy metaphorical Coalescence of their relationship and understanding, and how that kind of plays against/is paralleled to their not sharing any dialogue while he’s at Longbourn getting her father’s consent but I DIGRESS)
Anyway I guess what I’m getting at is, like. When you have an adaptation, especially across mediums and a significant period of time from the source text, the language has to be different in order to communicate the message, and I think it’s unfair to characterize it as a “flaw” that the film leans into historical inaccuracy, momentarily, for the sake of efficiency and effectiveness, especially since it doesn’t habitually engage with that historical inaccuracy. It would be one thing if characters had their hair down all the time, but they don’t! With the exception of Georgiana, who isn’t out, and maaaybe Lydia, who is inappropriate and probably shouldn’t be out, I can’t recall another character who ever has her hair down in public. And the closest otherwise we get to a man unbuttoned is when Darcy is delivering the letter to Elizabeth at Hunsford (which, again, is kind of that dreamy intimate liminal space that’s not quite reality so like…. Is he even Actually present being underdressed or is it just that he is metaphorically underdressed in the sense that he’s baring his soul and being honest in a very vulnerable and risky way? Again I digress.)
Anyway the point is: the Very Educated Austenite viewer is going to see Lizzie with her hair down and be like, damn shouldn’t this be rated R for Reputation-Ruining? But the average audience member is going to see Lizzie with her hair down (for the only time in the film, juxtaposed against Bingley and Caroline and Darcy all looking very polished and breakfast) and be like, wow I guess Lizzie is kind of a free spirit compared to these people. Which is ultimately what the scene is about, is showing that Lizzie values propriety, but she loves people more than she values propriety, and she does have a certain way of being that doesn’t always line up perfectly with what’s expected of her, and that’s precisely in character.
