It makes perfect sense to lump Nene and Kim in together. They were the circus attractions that drew so many into the Housewives universe, and the linchpins that made Atlanta become the biggest in the franchise - a show that let's not forget had DaShawn and Lisa tasked with getting us all invested.
Both completely lost what made them so endearing, as soon as they found something which they respectively deemed better: a man, for Kim; and work as an actress, for Nene. And the two new chapters came along for both at the same time, signalling the end of an iconic Housewives run. Although of course, neither woman needed to distinguish the beloved side to their characters in the pursuit of anything new. They could have had it all - and gone on to have ten legendary Housewives seasons instead of just the three.
With Nene, the change is the most baffling. Ryan Murphy cast her in two roles because, like the rest of us, he fell in love with the Nene he had seen on TV. She's a natural comedienne - and when she's being funny, she's undeniably a natural star, too. But as soon as Hollywood came calling for that Nene, she tried to shake off as much of that charm as she could, and attempted to polish herself into something else entirely. So Hollywood was left with someone it didn't ask for, and us viewers were left with someone we know wasn't being real. You can sort of understand the beginning of the downward spiral that followed, because of course the ego is going to take a hit, and of course the insecurities are going to creep in as more new women join the cast in Atlanta. But I just can't understand how she wasn't ever able to see that she could have turned it all around for herself in literally what is the easiest way possible - just being herself again. Obviously we still got to see glimpses of early-season Nene in later seasons, cos that's who she really is. But the guard was up 90% of the time, for reasons only she will ever know (though she probably never will know, because she's the most unlikely person to ever treat herself to a bit of introspection). And whenever she deemed that guard to be compromised, she became an even bigger monster. So nasty. So rude. She had ample opportunity to finally come to that realisation - that she needed to revert to self. Genuinely, at the start of every new season, viewers were waiting to welcome old Nene back, should she choose to show herself again. But by the last season (though probably, a few seasons before, in all honesty) it was painfully clear that she'd become a totally lost cause. Good riddance to the new Nene.
Kim, I guess, just felt that she'd changed as a person when she finally found love and started a new family with him. That, coupled with getting her own show, obviously made her feel that she'd become better than continuing with the Housewives drama. But once she checked out with the show, we checked out with her. Gone was that foul, comic book, drag queen caricature of a woman that, along with Nene, made seasons 1 to 3 of Atlanta so essential to watch - and which, also along with Nene, she's never been able to fully tap into since.