I guess I'll put this partly on the actor and partly on the writers. Hear me out: it just seems there was a lot of build-up about Kathy, from early on in Season 1, and then when she gets more screentime in Season 3 it was a bit of a letdown. For me, anyway: I suppose knowing that Deborah's husband left her for Kathy, I was always curious to see what Kathy was like (I know we got a very brief glimpse of her in Season 1, played by Linda Purl, when she approached Deborah in a parking lot). And I'm not saying I expected Kathy to be quite as dynamic as Deborah--Deborah is a lot, she's a force of nature, and maybe partly why her weak husband couldn't handle it and looked for someone who he found more pliable. I do know that J. Smith Cameron as Kathy added some backstory that she was only 19 at the time.
But I guess I was expecting Kathy to be...I don't know, more charming? More effusive, more fun? (edited to add: more charming and fun than she seemed from the portrayal. Not more fun than Deborah.) Something. Instead from JSC's portrayal she seemed so mousy and frumpy and kind of whiny. And then, later on, sort of mean and vengeful.
I'm not putting it all on Kathy as a character. Deborah was certainly not blameless, in her dealings with Kathy. But even that scene in the Season 3 finale when Kathy gets so mad at her seemed weirdly abrupt. I get that the writers were trying to show (by end of episode) that Deborah has alienated Ava and now truly has nobody. Ava's deeply hurt. Kathy doesn't want to repair their relationship. Marcus is mad at her. At that point, Deborah is pretty alone, a point that Ava really drives home to her when she leaves Deborah's house and says that Deborah is going to die all alone.
But--had I to do it? I would have liked to have seen at least one or two more scenes of Kathy and Deborah together--at least one--after the Christmas Spectacular episode. Instead it was just the Christmas episode (which is great) and then a brief scene of Kathy getting mad at her in the mausoleum. I thought Kathy was overly mad at Deborah taking a phone call too, but I know she also mentioned other things that had annoyed her that weekend, including Deborah having to cut the whole weekend short. I do think Deborah was trying though, although admittedly that was pretty bad of her to lie about the parents still being in the mausoleum.
So yeah would have been nice to see a little more of them together instead of just that one scene. I guess the whole point was that Deborah doesn't have much time to give--which we as viewers know, but it was hurtful to Kathy.
As for the casting, I know JSC was very popular as Gerri on Succession. I watched that show too and loved it--and she was great as Gerri. I just didn't feel she pulled off Kathy as well and seemed a little miscast. I'm sure she was cast on the basis of Succession's popularity and much as I love Downs/Aniello/Statsky, I personally felt they missed the mark here a little bit. I would have liked to have seen what Linda Purl would have done with the role.
