Yeah, she falls out with/discards too many people for there to be no substance to the plethora of articles on her.
What might be underlooked is 'the Karen' aspect, ie. the entitled american woman.
Historically 'the Karen' refers to difficult white women in america using their white privilege to inflict harm on non white people, but in its wider usage today it also refers to people of any race in america who are difficult/demanding ("I demand to speak to the manager" types).
She comes across as a Karen, ie. difficult and entitled. Despite Harry's aristocratic background he has never come across as difficult or entitled, until he got together with her. Now its "my daddy never pushed me on a cart" (despite pictures showing otherwise), and all the constant self absorbed 'woe is me' stuff in interviews/books that never appeared until he met her.
He isn't the sharpest as is well documented, which leaves him open to being easily manipulated/led. His personality has been transformed since he has been with her, and when he speaks that same self absorbed trait we associate with the Karen is there.
I think there is a definite clash of cultures. You couldn't envisage Kate being 'a Karen'. There just isnt that level of equivalent here, even in aristocratic circles.