I like that besides Lady Catherine, pretty much nobody wrong-headed has any sort of come-uppance in this book. Wickham gets a bunch of money. Mrs. Bennet gets her daughters married off to wealthy dudes. Even Lady Catherine doesn’t get a come-uppance so much as she didn’t get something she would have liked. The bad guys, if you can call them that, do pretty well. And Lydia is the best of all.
Not only did she not learn anything at all, but she’s actually quite pleased with her cleverness. If Lydia was the protagonist, the moral of the story would be “Do whatever! Go ahead!” I suppose you could imagine that her and Wickham have an unhappy marriage afterward and maybe you are supposed to do that. But don’t! It makes Lydia’s story arc a lot funnier and also increases the depth of Mr. Darcy’s good deed.
I didn’t mention Caroline Bingley among the antagonists even though I guess she is kind of a minor one. But she’s just looking out for number one. You keep doing what you’re doing, Caroline!