I was sick last week and listened to this boxset on audible.
My nostalgia brain loves these books (and childhood me would have given 5 stars for sure), but the underlying moral of the series about the importance of conformity is pretty much antithetical to my personal politics.
Girls bully each other and this is endorsed by the narrative. Characters who are coded as coming from a working-class background (e.g. Jo's father) are cast as vulgar, offensive, and embarrassing. EVERYONE is white, and seemingly only four countries exist in the world (England, Scotland, France and America) - this is despite the book being set in the years (so far as I can tell) immediately after WW2.
All of this pretty standard fare for Blyton, so if you're familiar with any of her other work, you probably know what to expect.
On the other hand, I will say that my adult queer heart very much enjoyed tomboy Bill, and her 'friendship' with Clarissa. Bill is probably my favourite Blyton tomboy :).