For the past several years (and perhaps longer) in the P&P fandom I've seen a lot of people who want to rehabilitate Mrs. Bennet: like, sure, she's uncouth and seems greedy, but it's because she cares so much about her daughters' futures; her situation is actually really stressful and uncertain and she's powerless to change it and her husband makes fun of her, and so it's natural that it would cause her to be anxious all the time; maybe she doesn't have the intelligence or social awareness to understand that her behaviour is actually harming her daughters' prospects, but at least her heart is in the right place.
I'm usually not the type of person who argues that fandom is actually being too nice to a female character, but in this case I don't buy the counter-narrative (which I think is popular enough at this point to be fanon / a narrative in itself) about Mrs. Bennet.
For one thing, she was never really powerless in this situation. These people are rich even for gentry. Mr. Bennet's income was always good, at 2,000 pounds per annum (even though I can't believe he isn't neglecting some practices that could raise it higher). Mrs. Bennet had 4,000 pounds from her parents and a further 1,000 from Mr. Bennet. Invested in the 4 per cents (for example), this is 200 pounds per year in pin money that Mrs. Bennet could spend without touching the principle of her dowry, and without affecting Mr. Bennet's income. This is more than some people's entire yearly incomes.
The picture of Mr. and Mrs. Bennet that we get in P&P is not of people who are helpless against their circumstances, but of people who are extraordinarily neglectful. We're told that:
Mr. Bennet had very often wished, before this period of his life, that, instead of spending his whole income, he had laid by an annual sum, for the better provision of his children, and of his wife, if she survived him. [...] When first Mr. Bennet had married, economy was held to be perfectly useless; for, of course, they were to have a son. This son was to join in cutting off the entail, as soon as he should be of age, and the widow and younger children would by that means be provided for. Five daughters successively entered the world, but yet the son was to come; and Mrs. Bennet, for many years after Lydia’s birth, had been certain that he would. This event had at last been despaired of, but it was then too late to be saving. Mrs. Bennet had no turn for economy; and her husband’s love of independence had alone prevented their exceeding their income.
We also know that the "continual presents in money which passed to [Lydia] through her mother’s hands," plus her allowance and food, amount to about 90 pounds per year. Rather than saving up from the beginning in case the entail is not broken, rather than beginning to save once it's clear a son will not arrive, rather than making Jane's dowry the full 5,000 from her mother (which would be something) and saving up for the younger girls' dowries thereafter—which is what would be typical, and that's why Lady Catherine was so shocked that all the girls were out at once—Mrs. Bennet's housekeeping, dress, the girls' allowance, presents of money over and above their allowance, plus whatever Mr. Bennet is spending money on (and other expenses relating to servants, carriages, maintenance &c. which are unavoidable), add up to their entire income. The only reason why Mrs. Bennet doesn't overspend even that is that that's where Mr. Bennet puts his foot down.
Mrs. Bennet is actively harming her daughters' prospects, not even of marriage, but of living respectably if they don't marry, because she doesn't have the temperance not to spend all of the income that is allotted to her. It is the role of the woman in a marriage to take charge of the housekeeping, servants, cooking, furniture, and all expenses relating thereto (plus certain attentions to her tenants and any living in genteel poverty in the area, though presumably this will depend on her income and whether there's a parish church with a parson's wife who's doing some of these things). She's an adult who should be competent to manage these things in a reasoned way without needing to be dictated to.
It is supposed to be the role of the woman in a marriage to take charge of her daughters' education—and yet Mrs. Bennet did not hire a governess, and Elizabeth says that she didn't spend much time teaching her daughters anything (it's not clear to what degree she's educated herself). Granted, the girls did have masters—but, from the sounds of things, that was only if they requested them. No one was required to learn much of anything, which will probably further harm the marriage prospects of the girls who "chose to be idle."
I think the "point" of Mrs. Bennet is that she is one half of one type of bad marriage which the novel illustrates, in contrast with the Gardiners' marriage. These marriages are two possible models for the Bennet daughters to look to. At one point, Elizabeth's prospective marriage is explicitly compared to her parents', with her in the role of her father: Mr. Bennet says "My child, let me not have the grief of seeing you unable to respect your partner in life" (emphasis original).
We might wonder whether Elizabeth saw herself potentially in the role of her father, in a marriage that was very intellectually unequal, when she rejected Mr. Collins; or whether she also saw herself in the role of her mother, married to a man who insults and doesn't respect her, when she rejected Mr. Darcy. Ultimately, she accepts Mr. Darcy after she realises that he is nothing like her father; that he is diligent in attending to his responsibilities, and that he does evidently respect her mind.
This isn't me defending Mr. Bennet, who is also a bad parent and a bad spouse. I do, however, find it a little disturbing when people suggest that Mr. Bennet is at fault for not controlling or curtailing his wife. His wife is a grown woman. Surely we don't actually believe that a situation where a man is legally in complete control over his wife, merely because he is a man and she is a woman, is in any way natural, moral, or just? (This also goes for people who suggest that Mr. Bingley needs to get his sister 'in line' 😬😬😬.)
Mrs. Bennet should be competent to manage her household and her daughters. Given that she's not, yes, Mr. Bennet, according to Georgian and Victorian ideas of the role of a man in a marriage, "should" have stepped in and started dictating to her. But I don't really think that's what Austen is suggesting went wrong here. The models of good marriages we have—the Gardiners, the Bingleys and Darcys after their weddings—are all ones in which the women were basically sensible people to begin with. In the latter two cases, we are told of particular ways in which the men stand to benefit from some mental quality of their future spouse (Elizabeth's good humour and ease in company; Jane's steadiness and determination).
The ideal which some Georgians had of a husband's role being to shape his wife's intellect doesn't seem to be what's being advocated here. If Mr. Bennet made a mistake, it was in marrying a silly, selfish, ill-tempered woman to begin with, not in failing to browbeat her into submission once he found out that she was silly, selfish, and ill-tempered. The idea is that you should choose your spouse carefully. But that message doesn't work if Mrs. Bennet is just a woman in a difficult situation who has her heart in the right place.
