This has always been my favorite JA quote probably because I was brought up to be a Southern Belle and I know this attitude still prevails today. It really resonated with me. That boys do not like smart girls is something you are brought up to. You are expected to act stupid all your life though it is not necessary to actually be stupid. Jane Austen tells us not all men share this flaw. Some only want their women to be ignorant so that the man can feel smarter by forming her thoughts (a reference here to Mansfield Park and Lady Bertram-there being a question as to why Sir Thomas would marry such a vacant person)Our Catherine is in just this relationship to Henry. She is very ignorant and he is well informed. He would find this an attractive especially when combined with her other positive traits.
'She was heartily ashamed of her ignornace-a misplaced shame. Where peole wish to attach, they should always be ignorant. To come with a well-informed mind, is to come with an inability of admisintering to the vanity of others, which a sensible person would always wish to avoid. A woman, especially, if she have the misfortune of knowing anything, should conceal it as well as she can.'
Jane Austen is not making fun of women, she is making fun of men.