I've been thinking of doing this thread ever since Denise Gough's comments about her character being mean to children, but I refrained since we weren't sure if she was playing Letty and there was already so much controversy around the upcoming Magician's Nephew movie, why add more? But now it's looking more like Gough is playing Letty and fans are talking about it in the comments section of Narniaweb's story on that, so I thought we might as well discuss it here too. 

Since I'm lazy, I'll just quote the relevant comments which all had good points. Normally, I'd hesitate to quote them here that since the comment section is less moderated than the forum, but these comments were pretty polite. 

Forrest:

To be fair to Letty, while firm and tough (which described not her treatment of others, but her toughness in being thrown across the room), she shows concern for Digory’s well being, trying to shield him from her rotten brother:

“Whenever [Uncle Andrew] tries to say anything to me at meal times — he
never even tries to talk to [Aunt Letty] — she always shuts him up. She says,
‘Don’t worry the boy, Andrew’ or ‘I’m sure Digory doesn’t want to
hear about that’ or else ‘Now, Digory, wouldn’t you like to go out and
play in the garden?'” ….and she refers to her dying sister as, “But poor, dear little Mabel!”

I don’t think “mean to children” fits her as written.

Bolton:

Do you really think Gerwig would take a fully realized book character (and a female one at that) and reduce them to one that is a one-note, mean character? Even if she plays up a bit of Letty’s strict, “mean” persona for the children (which I can see in the book, especially from a child’s perspective), I can’t picture her as being a simple baddie without complex character motivations where she doesn’t care for protecting Digory or her sister.

Forrest:

I have no idea what Gerwig is doing with this character. I’m only comparing and contrasting what the actress has said versus how Letty is written. I get no sense that Letty is “mean to children” in the book. I didn’t say nor do I think Letty will be portrayed as a villain, either. Just that she’s not mean, not as Lewis wrote her.

F:

I really hope GG doesn’t intend to make Aunt Letty an unsympathetic character in the film. The last thing we fans want is to side with the Witch during their confrontation scene where Letty tells the witch off and gets thrown.

Bolton: 

I don’t think you need to worry about that. Gerwig writes fully fleshed-out, real characters, so the idea of Gerwig taking a well-intentioned female character in the book and making her into one that is unsympathetic to the point we’re rooting for the witch doesn’t make sense.

F:

This actress describes her role as being “mean […] to children“. Maybe it’s just hyperbole, but it doesn’t make sense for Aunt Letty, given that no one in the story (save Uncle Andrew) would think of her as ‘mean’. Yet I’m not really worried about this potential change; I’ve got bigger fish to fry regarding this Netflix-Narnia ‘revision’.

What do you guys think? The literary Aunt Letty may be stuffy and Digory doesn't like her much but she's also kind of cool in her own way. I'd be disappointed to see her made a villain and I wouldn't expect it, but Denise Gough knows more about this movie than any of us do. 

Crazy thought: Maybe they're reversing Uncle Andrew and Aunt Letty's roles in the adaptation.